Coast (2005) s01e01 Episode Script
Dover to Exmouth
1 The white cliffs of Dover, starting point for an epic journey around one of the most complex and fascinating coastlines in the the world, our own.
The coast is where the story of an island nation, its history, its geography, and above all its people, is told most vividly.
This is life on the edge, the coast as you've never seen it before.
It's easy to think that the coast is merely where the country stops, where the land falls into the sea.
In fact, our coastline is at the very heart of our shared history, the source of so much national wealth, and where empire was born.
Many of us work here.
Even more of us come here to play.
But few of us have ever travelled its entire lengthuntil now.
This is a once-in-a-lifetime journey.
We'll be exploring the coast of England, Wales, Northern Ireland and Scotland, uncovering the treasures that have made us the island nation we are today.
But to fully appreciate the diversity of our coast, will take a diverse range of skills, so I'll be travelling with a small, dedicated team of experts.
Writer and historian Neil Oliver will explore the human stories behind the history.
Zoologist Miranda Krestovnikoff is our guide beneath the waves.
Anthropologist Alice Roberts will be grappling with the actual stuff that makes up our coastline.
Archaeologist Mark Horton is going to dig up the hidden histories along our familiar shores.
And me? Fantastic! Well, I just can't wait to get started.
An 11,700 mile adventure, this is the story of Coast.
The first leg of our journey takes us the 330 miles from Dover to Exmouth, a coastline pockmarked by a legacy of invasion and war.
This is Britain's frontline.
Many of our neighbours have had a crack at invading here.
One or two even succeeded.
Since Roman times, we've been fortifying this coast, building chains of linked defences, grand castles, Saxon shore forts, evolving and reinventing them as the enemy got stronger, but always looking nervously out to sea.
This is a Martello tower.
It's number three, just outside Folkestone.
Number one Martello tower is over there, and nestling down in the hollow is number two.
And stretching away along the south coast in that direction, another 71! All 74 towers were built in the early 1800s at a time when Napoleon had overrun most of Europe and saw no reason why Britain should be left out of his grand design.
Oh, it's rather beautiful.
There's not a straight edge to be seen on the ceilings or the walls, it's a room entirely full of curves.
And look how thick the walls are.
Each of these towers was built from half a million bricks, and they might look round, but actually it's elliptical, built thicker on the seaward side to withstand the cannon fire of an attacking French navy.
The building of 74 towers was a hugely ambitious engineering project, but ultimately they were never put to the test.
In 1805 Napoleon's seemingly unstoppable march through Europe was halted when he was beaten by Admiral Lord Nelson at Trafalgar.
The final nail in the coffin came ten years later at Waterloo.
Napoleon was a spent force.
For the next 100 years, war, at least as far the British were concerned, was something that happened a long way away, never on our own shores.
That long spell of peace at home came to an abrupt end with the outbreak of the First World War.
The German aircraft that bombed London in 1917 were primitive, but they proved that warfare had taken to the skies.
When the war was over, military strategists had to face an alarming truth.
The waters around our shores, dominated for over 500 years by the navy, could now just be flown over.
In future, wars would be won or lost from the air.
The success of our defence would depend on early warning of attack.
And before the advent of radar, the best chance we had of getting that early warning was one of these, monolithic upturned concrete soap dishes.
Known as sound mirrors, these top-secret constructions, built between the wars, were designed as giant ears to listen out for approaching enemy aircraft.
Most of them have been demolished, vandalised or have simply rotted away, but remarkably this one just outside Folkestone is still standing.
And just 18 miles further down the coast, at Denge near Dungeness, there are three more sound mirrors.
Considering they were abandoned more than 70 years ago, they're in remarkable condition.
It's hard to believe that these long forgotten relics of war played a vital role in the defence of the United Kingdom.
Great to meet you.
'Richard Scarth has dedicated 20 years of his life to the study of the mirrors.
' Richard, they're incredible! The sound mirrors were the life's work of one man, Dr William Tucker.
Richard, by the time Tucker came here, he'd been working on sound-detection equipment for 20 years.
He had, and the results of their work was this magnificent structure here, the biggest sound mirror of all.
This is a monument to his life's work.
Yes, it is, yes.
It is absolutely fantastic.
It's enormous.
In their day these mirrors were the cutting edge of military hardware.
70 years on, they lie abandoned and the secrets of how they work forgotten.
With the help of the National Physical Laboratory and the Open University, we're going to unravel their mysteries and get them working again.
Very little technical information has survived, so our scientists are going to have to work from scratch.
And their first discovery is that the mirrors are much more complicated than they appear.
OK, so it's ready to go, then.
Yeah, cos that's as far as we're going up.
In the 1930s, as Tucker's team struggled to perfect the sound mirrors, tension was rising across Europe.
And in Britain the government began to assess the country's readiness for war.
As part of those exercises, aircraft were flown towards the sound mirrors to assess their early-warning capabilities.
We've got a Tiger Moth standing by to do the same thing, but before it can take to the air, we've got to discover how the mirrors actually work.
A little bit more, try a little bit more.
By setting up two microphones - a red one listening to the mirror and a control microphone marked with blue, well away from the mirror - our scientists hope to reveal the sound mirrors' secrets.
Well, what we're using is a single tone, and so what that shows up on this graph is a single peak, and you can see this single peak here.
A very dramatic spike.
On the top graph Which is the red microphone.
At the sound-mirror focus, you can see that we've got a level which is up around 70-80 decibels, in fact.
On the blue graph at the bottom That's the microphone standing in the open.
Yep, you can see the level's much lower, down at about 60 decibels.
So the sound-mirror microphone is picking up much more sound.
It's amplifying it by as much as 15 decibels.
So this is exactly what Tucker's physicists would have been doing all those years ago.
Exactly.
Our first eureka moment.
The sound mirror makes the tone almost four times louder.
In the simplest case, an aeroplane could be coming in, sound waves coming from that aeroplane are going to hit the mirror at different points.
And where those reflected rays meet is what we call the focal point, and you'll get an increase in the sound level at that point.
But if say, for example, the aeroplane was off axes, sound travelling from that is going to bounce off the mirror.
But this time the angles would have changed, the focal point has now moved down to here.
If you simply move your microphone, you can get not only an early warning that a plane's coming in, but also the direction.
Which is the essence of early warning.
Absolutely.
That's got enough water out, we can now see how the mechanism worked, can't we? Yes, and you've got to imagine that underneath here was an operating room, and there's a man sitting in there who's got control of this apparatus, which is designed to move a trumpet which was on the end of that arm over the focal area of the mirror.
The mirror's designed to focus sounds just a few feet in front of it, and so the collector went round at that plane and picked up the sounds, hopefully, of a distant aero-engine.
And when he listened in his stethoscopes, when he got to the place where it was the loudest, that was the direction the aircraft was coming.
Of course the idea was that there would be several of these mirrors up and down the coast and they could work together to a control centre, and they'd get cross bearings, which would give them more accuracy.
At the heart of this larger network of mirrors was Dr Tucker's 200 ft wall.
Armed with the understanding we've gained from our experiments at the smaller mirror, our scientists are now ready to use Tucker's wall for our own early-warning test.
Our Tiger Moth will head out to sea, then turn back and approach the mirror along its axis, which we've marked with a white sheet.
Flying at 500ft and 90mph, this mimics one of the government tests from the 1930s.
I'm gonna put these headphones on, which are wired up to the red microphone in front of the mirrors, so if Tucker's wall works, I'm going to hear the plane first.
Yes.
The piston-engined Tiger Moth of the 1930s sounds exactly like the planes that Tucker's men would have been listening out for.
The tension's really unbearable, just waiting.
Complete silence.
Headphones are silent I can't see anything yet.
ENGINE HUMS I'm getting something! I can hear it! And some spikes! I can't hear a thing without them on.
Nothing on the blue traces.
Blue trace This definitely isthe Tiger Moth, there's its fingerprint.
Fantastic! ENGINE HUMS Now I can hear it really clearly.
Yeah, here he comes.
Really loud now.
There it is! Right above us at last! Tucker's machine beat the human ear by a long way.
That was fantastic.
70 years on, it still works.
So we got nearly 40 seconds or about a one mile advance warning.
Not bad for a 70-year-old piece of concrete, but nowhere near Tucker's best-ever results of over 20 miles.
But in 1933, while Dr Tucker and his team were toasting their success, other scientists were measuring a BBC radio signal as it bounced off a Hayford bomber.
After only five months in development, this discovery, the earliest form of radar, was was detecting planes over 40 miles away, twice the distance that the sound mirrors had ever achieved.
It was all over for Dr Tucker's acoustic detection system.
By 1937, the sound mirrors had been abandoned.
Well, what became of Dr Tucker? For some reason that nobody seems to be able to explain, he was more or less forcibly made to retire, and one of the last things he was asked to do was to destroy the mirrors by blowing them up, but thank goodness he didn't obey his orders.
Dr Tucker's retirement may have been the end for the sound mirrors, but nevertheless they were to have a profound effect on the course of the Second World War.
The reporting structure that Tucker developed for the mirrors was copied by the radar team and led directly to their success in the Battle of Britain.
The 7.
45 from Hastings to London.
Not an obvious choice for a coastal journey.
But something rather interesting has happened along this stretch of the coast.
It's easy to think of our coast as unchanging.
In fact, it's constantly in flux.
We are now approaching Pevensey Bay.
Would customers please note? Erosion is eating away at much of our famous landscape.
And yet here in Pevensey Bay, different forces have been at work.
Since William the Conqueror landed almost 1,000 years ago, the shoreline has changed beyond recognition.
Rather than eroding, it's been growing.
As much as a mile-and-a-half has been added, reclaimed from the sea.
Land reclamation, or "inning", has been going on here since the 13th century, when the local church authorities would pay to have the land drained and turned over to agriculture.
But just beyond Eastbourne, where the commuters and I part company, is Beachy Head, the flipside of coastal change.
At 163 metres above sea level, the cliffs at Beachy Head are the highest chalk sea cliffs in the United Kingdom.
The question is, as they say in the soap powder ads, how do they stay so white? The unhappy answer - erosion.
The cliffs barely have time to get dirty before the wind and waves strip them away.
Up to a metre is lost every year.
In 1999, the Belle Tout lighthouse made headline news when the owners paid nearly ï¿¡200,000 to have it moved back from the cliff edge to prevent it falling into the sea.
At the current rate of erosion, it's a procedure they'll have to repeat in 2016.
And again in 2033, 2050, 2067, 2084 20 miles further round the coast is Brighton, a resort with a long established reputation for hedonism.
For centuries, it's played host to an invasion of Londoners who want a bit of sin by the sea.
Or in it, for that matter.
Its long beach, that stretches from Brighton to Selsey Bill, it's a playground for holidaymakers.
But beyond the candyfloss and deckchairs, there's another world - a world beneath the waves that most of us never get to see.
This journey is not just going to take us along the coast, but into the seas around our islands, to reveal the extraordinary diversity of our marine wildlife .
.
a subject that zoologist, Miranda Krestovnikoff, has been studying all her working life.
I've dived all over the world, but it's easy to forget there are some stunning wildlife dives much closer to home.
But when two local divers, Robert Walker and Paul Parsons, told me there was a good chance of photographing cuttlefish just offshore here, I was a bit sceptical.
So are we expecting to see activity like this if we dive today, or is this unique? I think we will find cuttles.
We may not get this activity, because everything has to be just right, but we should be able to find cuttlefish, hopefully mating.
All this equipment and all this effort, I really hope it's worth it and there are cuttlefish down there.
The vis may not be that good but once you get your eye in, there's loads to see down here.
Here's a tube worm.
This feeds by just picking up whatever's floating past in the current.
If I just reach out and touch it with my finger, there you go.
It's retracted its tentacles.
We're only a few metres out and a few metres deep.
There's so much marine life here.
This little dragon-looking creature is a pipefish.
They look a bit like sea horses, they're related to sea horses.
Oh look! There's a cuttlefish.
Exactly what we wanted to see.
They're such exotic looking creatures.
You'd never imagine to find something like this right here in British waters.
It's very big.
A couple of feet long.
They look sort of alien.
A really, really unusual shape, with those big eyes and this floating skirt.
Really odd-looking creatures.
Cuttlefish are in the same family as squid and octopus.
Sometimes known as the chameleon of the sea, they can change their body colour and patterning to mesmerise their prey.
I've just realised there's a change, and up there there's two tentacles, and they're going a darker colour.
It's obviously feeling a little bit threatened.
That's its threat posture.
Off he goes.
Gosh, what's he got? Goodness me, he's just grabbed a crab! That's amazing.
Don't think I've seen that before! Cuttlefish have a sharp parrot-like beak and a venomous bite, which will make short work of this crab.
As the sea warms in spring, cuttlefish invade these shallow waters to mate and lay their eggs.
This part of the south coast is a real hot spot for them.
Male cuttlefish dazzle the smaller females with their striped patterns and flowing tentacles.
They mate head to head, with tentacles entwined.
After mating, the male cuttlefish guards his female as she deposits her eggs, dyed black with ink to deter predators.
This cuttlefish invasion lasts all summer, but with the water cooler, and their life cycle complete, both males and females die, leaving their bones to be washed up on the beach.
Truly amazing.
Diving this close to the shore, and seeing these weird, weird creatures.
That's a pretty incredible dive.
We're almost halfway through the first leg of our journey to Exmouth.
About 130 miles from Dover is the city of Portsmouth, the place with centuries of maritime history, a fair proportion of which is connected directly or indirectly with the Royal Navy, down there.
Her Majesty's naval base, Portsmouth, currently harbours two thirds of the Navy's surface fleet.
But the city's proud naval tradition goes back nearly 1,000 years, with many decisive military campaigns being launched from here.
The fleet's biggest engagement of recent years was in 1982.
On 5th April, the first ship set sail from Portsmouth on the 8,000 mile journey to the Falkland Islands.
The question is, why here? Why was Portsmouth chosen above other ports on the south coast to be home of the Royal Navy? Archaeologist Mark Horton is in the Historic Dockyard to find the answer.
Morning.
Morning.
Shall we go for a trip? Yes, climb aboard.
My guide, Roy Rolfe, started off by explaining how the geography here works to make this place an ideal port.
Crucially, the huge expanse of water in Portsmouth harbour is only accessible through a small entrance.
Right in the entrance now, you can see it's very narrow.
And presumably defensible because it is so narrow.
That's right, yes.
We're now actually out into the entrance channel to Portsmouth Harbour.
And on the shore of the Isle of Wight.
The Isle of Wight is one of the main reasons why this is such a good harbour.
So that's as a sort of protection - despite the fact we can see the wind coming in, it's quite sheltered.
And it also means the harbour is always usable.
You don't get the sort of weather you could get at Dover sometimes, by the breakwater, where it's something of a lottery to get in and out in very bad weather.
The harbour at Portsmouth has a lot to recommend it, but in many ways its trump card has nothing to do with its physical geography.
And everything to do with politics.
For much of our history, England was at war with her continental neighbours.
First the French, then the Spanish, and then the Dutch.
In those battles, it was considered important to have a harbour as close as possible to the enemy.
For the Spanish wars, that meant Plymouth.
For fighting the Dutch, Chatham in Kent was best.
But it was the French wars that were begun by Henry VIII that really made this place important.
Henry created the Royal Navy in 1525, and decreed that Portsmouth should be its home.
Through fighting the French seven times in 290 years, Portsmouth grew from 1,000 people in 1545 to over 30,000 in 1800.
Now the docks were home to 684 ships, and were the largest industrial complex in the world.
But things for Portsmouth were about to change again.
Just listen to that wind to the rigging.
The Victory, where Nelson defeated the French 200 years ago at the Battle of Trafalgar.
But ironically, it was that victory against the French that changed the role of Portsmouth for ever.
From the base where we fought the French, to the place where we patrolled the world and fulfilled our imperial ambitions.
For the next 200 years, Portsmouth's growth was driven more by technological innovation than military need.
The move from sail to steam in the 19th century saw the biggest expansion.
It's the sea just the other side of those somewhat rusty gates.
This is the number six dry dock, one of around 20 here.
Portsmouth was not just the centre of the naval operations, but also an important dockyard, where ships could be built, and comfortably repaired.
As the ships got larger and larger, so the dry docks themselves had to get bigger and bigger to keep pace with technological change.
If the 19th century saw Portsmouth grow with every new technology of war, the 20th century saw the benefit during two world wars.
In the 21st century, warfare continues to change.
So what is the future for our oldest naval base? For the surface navy, the escorts and the aircraft carriers, this is where it's all at, yes.
And does it still work as a harbour? Is it suitable for the modern navy? Oh, very suitable.
There's a large investment programme going on to make sure it continues to be suitable, continues to evolve to meet modern requirements.
Portsmouth is here because of medieval monarchs, Henry VIII and the French.
I think the reason he chose it is because France was the enemy.
Today that is not the case.
Do you think in 500 years' time, there will be a base here at Portsmouth? As long as we've got a navy, it will still be here.
Leaving Portsmouth behind, we're continuing west.
18 miles further round is this coast's most important commercial port - Southampton.
Massive liners like Queen Mary II make regular trips to New York from here.
But more infamously, in April 1912, the Titanic's maiden and only voyage began from this port.
Southampton is also the starting point of historian Neil Oliver's flight to Alderney, the third largest of the Channel Islands and the place on our shores which bears the scars of invasion more vividly than anywhere else.
The British Isles comprise over 6,000 islands, many of which we'll visit on this journey.
But unlike the Scottish islands, or say, the Isle of Wight, the Channel Islands are technically not part of the United Kingdom.
Even so, they come under the protection of the British crown.
65 years ago, that protection was tested to breaking point.
During the Second World War, the Channel Islands were occupied by German forces.
Alderney became home to four forced labour camps and nearly 7,000 slave labourers.
Those are the bare facts.
What they don't tell you, though, is what the slave labourers were really doing on Alderney, and what their day-to-day existence was actually like.
That's it, I'm through.
No passport control, no customs, because I'm still in Britain.
By 1940, with the German forces in control of Western Europe, the first invasion of British soil in nearly 900 years looked inevitable.
7.
5 miles from the French coast, the people of Alderney were going to be the first Britons to be overrun.
CHURCHILL: We shall fight on the beaches, we shall fight on the landing grounds.
We shall fight in the fields and in the streets Of course, there were a few beaches that Britain wasn't going to be fighting on.
After the fall of France, the Channel Islands were in the front line and the British Army decided that the best move was to evacuate the islands and leave their fate in the lap of the gods.
So this is where it took place, then, the evacuation? 'Buster Hammond was among the first to be given the order to evacuate.
' Can you describe what that was like? I can't imagine the thought of leaving everything I've known.
I mean, when the door of the house that you're living in is opened - you never locked them anyway - and a man's voice shouts up the stairs "The boats are in, "you've got two hours to leave, "to board, one suitcase each".
I mean, what do you go to get actually in cases like that? We were more concerned about the cat.
When you were all down here waiting to get on the boats, what was the atmosphere like? No panic, no panic.
We just waited our turn, got on board the boats, just as simple as that.
I dare say there was a few tears here and there, naturally.
I mean some of the people had never been off the island.
The islanders were taken to England, uncertain when, or even if, they would ever see Alderney again.
Once that last ship had sailed, the island of Alderney was abandoned, and here, St Anne's, was a deserted ghost town.
Clothes left hanging in wardrobes, fires going cold in the hearth.
The whole place was at the mercy of whoever was coming.
Within days of the evacuation, Luftwaffe reconnaissance planes were circling the island like vultures.
Then on 2nd July, the Nazis landed on Alderney soil for the very first time.
The Germans had invaded an empty island.
It wasn't long before they began to implement their plans for Alderney.
It was one of the principal Channel Islands, and effectively they were providing offshore gun platforms for the French from the mainland of France.
In 1941, Hitler ordered the construction of huge bunkers like this, as well as gun emplacements and fortifications all over the island.
This tiny little door is the only way in.
It is a pretty impressive structure.
Look at the depth of the walls.
Two metres thick.
Concrete, reinforced.
There we are.
Turn through 90 degrees here.
Lead on.
On the right we've got an entrance defence position.
And this corridor then leads forward.
Daylight.
You get an idea of the panorama.
That is just brilliant, isn't it? What a view.
I'm beginning to realise what the concentration camps must have been for.
The scale of construction here is awesome.
They were labour camps for the building of these bunkers.
The masterminds behind this scheme were infamous German construction force, Organisation Todt.
The Organisation Todt cut their teeth on the building of the German autobahn system and the fortifications of the west wall in Germany.
So that by the time they came to the occupied countries of Europe, they were experienced in building this type of fortification.
So is this literally the book that you could work from to build your defensive position? Yes, absolutely.
It's the pocketbook carried by the engineers when they came to the site.
I love these artists' impressions of what your finished bunker is going to look like once the grass is back.
It's chilling how clinical these plans are.
Because however sanitised they look, you can never forget they were built by slaves.
The forced labourers who worked here for Organisation Todt were accommodated in four camps, all of them named after German North Sea islands.
There was Heligoland, Borkum, Sylt and right down there, Norderney.
Camp Norderney held over 1,500 prisoners from all over occupied Europe.
They were kept in filthy wooden shacks.
Today nothing remains - no clue to the story of what happened here.
One of the last surviving prisoners is 82 year-old Monsieur David Trat, a French Jew who was only brought here and spared the death camps of Auschwitz because his wife was a Christian.
HE SPEAKS FRENCH How were you treated by the guards here? "We were beaten with everything they could lay their hands on - "with sticks, spades "There were many men among us over 70 years of age "Hard physical work "We were accused of laziness, but mostly we were beaten out of hatred.
" How did you survive? Many would never see their families again.
No-one knows exactly how many died in the labour camps on Alderney.
The official figure is 437.
But many believe the death toll was much, much higher.
The surviving slave workers were finally moved from the island to camps on mainland Europe on 7th May 1944.
One month later, the liberation of Europe began, but the Channel Islands remained under increasingly desperate German occupation for a further year.
Finally, in May 1945, the Germans surrendered.
Buster Hammond was one of the first islanders to return home.
It was so exciting, and the thing that struck us most was the number of buildings that had been put up by the Germans, and when we came inside the breakwater, one of our local men, a Salvationist, put the trumpet up and played "Home Sweet Home".
It was just The sheer magic of being five and a half years late to come back.
For Monsieur Trat, coming back to Alderney is a more difficult experience.
This is the mouth of Poole Harbour, the second largest natural harbour in the world after Sydney.
With its warm micro-climate and spectacular beaches, the village of Sandbanks at the harbour mouth has the distinction of having the 4th highest land values on Earth, beaten only by New York, Tokyo and London.
A four-bedroomed house on this tiny spit of land goes for as much as ï¿¡2.
5 million.
The chain ferry takes about five minutes to cross between Sandbanks and Studland on the other side.
The alternative is a 26-mile drive around the bay.
And more than a million people make use of it every year, some of them to take advantage of the rather special freedoms available on Studland Beach.
My name's Keith Basham.
I live in Bournemouth.
I come across here to Studland because it's such a fabulous place to be, very relaxing and the views and the scenery here are unbelievable.
I think a naturist is somebody who enjoys the freedom and the relaxation of being naked.
It's not a sexual thing - it's purely a sensitive and sensual feeling.
We have an area devoted to naturists, and obviously the rest of the beach is for non-naturists.
It would be nice in a really hot climate where there's no problem with cold nights etc etc, but enjoying naturism on a beach - I don't think I could enjoy anything more special than that.
I do have friends that are not naturists, but I will be undressed and they won't.
They accept me as a naturist and I accept them as what we call a textile.
West of Studland Beach, the nature of this coast changes in the most dramatic way.
These chalk stacks, known as Old Harry Rocks, mark the beginning of the last third of our journey, and the start of 95 miles of cliffs and beaches known as the Jurassic Coast.
The history laid bare here belongs to the age of the dinosaurs at a time when this land mass lay thousands of miles to the south on the equator.
For anyone interested in the evolution of our planet, this is the best place in the UK.
Like the millions of visitors who come here every year, anthropologist Alice Roberts has a special place in her heart for this stretch of our coast.
The extraordinary thing about this length of coastline is that it spans nearly 200 million years of Earth's history - that's three geological time periods.
And for that reason, in 2001, the United Nations designated the Jurassic Coast a World Heritage Site, alongside iconic places like the Great Barrier Reef and the Grand Canyon.
In fact, though, the Jurassic Coast is a confusing name because, along its 95-mile length, there are younger Cretaceous and older Triassic rocks to be seen.
The Cretaceous rocks at the eastern end were formed at the time some of the largest dinosaurs roamed the Earth.
Further along, and further back in time, are the fossil-rich Jurassic rocks, created as the Earth saw an explosion of marine life.
And finally, at the far western end, are the very oldest rocks of this heritage coast.
The striking red Triassic cliffs were formed up to 250 million years ago.
What's unique about this area is that these three geological periods, which together make up the Mesozoic era, are laid out next to one another.
But the process that's created them takes some explaining.
Lovely! Thank you.
I've got three slices of cake in front of me.
This first one is going to be the earliest rocks we find along the coastline, the Triassic rocks laid down between 200 and 250 million years ago.
They're red sandstone rocks, laid down in the middle of a great arid desert.
The next layer is Jurassic.
Here we have a story of sea levels rising and falling and marine sediments being deposited - limestone, clays, that sort of thing.
Lots and lots of fossils in this segment.
This is between 200 and 140 million years ago.
Finally we have the most recent rocks, the Cretaceous rocks.
These were laid down in swampy environments.
Those represent between 140 and 65 million years ago.
If that was the end of the story, we would be standing up here and we wouldn't be able to see the Jurassic or Triassic rocks underneath.
In fact, what happened during the Cretaceous period was that the whole thing sank down in the east, so that we end up with in fact all of these layers pointing up to the west end.
And then it has eroded, so if I represent the erosion by cutting through the cake at an angle like that Then what we've got is the land surface of today.
We start in the east at Old Harry Rocks, and we walk through cliffs that are Cretaceous, then suddenly we find ourselves walking along Jurassic cliffs, and finally into the oldest rocks, Triassic rocks, until we get all the way to Exmouth at the end of this prehistoric walk along the coast.
And it is quite delicious! Here at Lulworth Cove, deep in the middle layer of the cake, the Jurassic rocks tower above the beach.
For nearly 200 years, they have been attracting visitors on the hunt for the fossils they contain.
But there's actually something hidden in these ancient rocks that is much harder to find.
Just to the west of Lulworth Cove is Stair Hole.
There I met Dr Andrew Hindle, a geologist who has been searching for the liquid remains of fossilised sea creatures - oil to you and me - for over 22 years.
It's not just an academic interest.
You're actively prospecting for oil here, aren't you? Yes, just like Sherlock Holmes, just getting all the information.
So you're looking at structures and trying to predict where the oil will be under the surface.
Yeah.
A colleague and I set up an oil company to look.
We think there are several hundred millions of barrels still here.
Several hundred millions? Underground in Dorset? Very close to where we're sitting.
That's amazing! Hundreds of millions of barrels of oil? With that number ringing in my ears, Andrew hit me with another surprise.
Just a few miles west of Lulworth Cove is an area known as Burning Cliff - for very logical reasons.
Apparently, one of the strata in the rock face has been known to catch fire spontaneously.
Which layer was it that was burning? It was these dark coloured shales you see down the base of the cliff.
It was this area here, which is largely landslip now and covered up.
That was the bit that was on fire.
But it wasn't the vegetation? It was the actual rock? That's right.
This Kimmeridge clay here is about 80% organic matter - fossilised plants and animals.
Algae and plankton that's been laid down at the bottom of the sea? That's right, and preserved.
They're very organic-rich.
That gives you the fuel source, if you like.
It's really strange.
We are actually looking at a section through a fossil fuel.
That's what a fossil fuel is.
That's absolutely right, yeah.
The Kimmeridge oil shale at Burning Cliff is named after a place just along the coast called, unsurprisingly, Kimmeridge Bay.
There we met Paul Farramond, a geochemist, who was going to show me on a smaller scale, what the Burning Cliff must have been like.
The oil shale are these bands here, which, where they're orange, you can see them higher up in the cliff as well.
Just break a bit off.
There we go.
Is that a big enough piece? Yeah, that'll be fine.
I don't believe it's going to set on fire - it's a piece of rock! I think you'll find it will.
It's just beginning to catch there.
As you see, lots of smoke comes off it.
It's definitely on fire! But, as you can see, it goes out quite easily.
And it stinks! It really is bad, yeah.
That's right.
You can see the oil coming off the surface of the Kimmeridge shale.
That's oil as we understand oil to be? Yes, absolutely.
The Kimmeridge shale was the source rock of most of the oil in the North Sea.
When you say source rock, you mean the same layer as we have here? Absolutely, yeah.
And that's the real magic of Kimmeridge oil shale.
This rock is the reason we have North Sea oil.
The same strata that are visible on the south coast are buried 3? kilometres deep, under the oil wells off the north east of Scotland.
Over millions of years at the high temperatures and pressures deep under the seabed, the oil shale produces oil.
In place of 10 million years at 100 degrees centigrade, we can do 30 seconds at 500 degrees centigrade and drive some oil off in the test tube.
If you wanna hold that in the tongs You can see it's not actually burning, it's just driving the oil off.
There you can see all that brown, looks like smoke.
It's actually just oil being distilled off the rock.
You can see droplets of oil around the side of the tube.
The brown stuff? That's actually oil that has been driven off.
Wow! This stinks as well! Yeah.
It's fascinating to see oil being produced in front of your eyes like that, but remember, Andrew is still looking in this area for the naturally occurring stuff.
30 years ago his predecessors were looking for the same thing, and just above the beach at Kimmeridge they struck lucky.
It's the last thing you expect to find in the middle of rural Dorset.
That's right.
Is it really just an experimental thing or is it producing on a commercial scale? It's very much a commercial scale.
They're producing 100 barrels of oil a day.
At current oil prices about 4,500 a day, so quite a significant income.
The find at Kimmeridge led to another near Poole Harbour.
Together these wells pump more than 2 million worth of oil out of the ground every day.
But in each of the last six years Wytch Farm has produced less oil than the year before, so for prospectors like Andrew the race is really on to get that next big find.
Spectacular geology isn't the only thing that the Jurassic Coast has to offer.
It is also home to several of our better-known seaside resorts, the biggest being Weymouth.
It's now a pretty Georgian town.
But it has a dark past.
It was here, far from the battle-hardened eastern end of our frontline, that the last truly devastating invasion took place - an invasion that resulted in the death of a greater proportion of our population than any war in history.
But it wasn't an army that arrived in June 1348.
It was the Black Death.
It's customary to blame its introduction on the rat.
But actually the carrier was a sailor recently arrived in this port from France.
By August 1348, two months after its arrival, the plague had reached Bristol.
A month after that, London and on into East Anglia and the Midlands.
In under a year, it overran Wales, then Ireland, then Scotland.
In 18 months, the Black Death killed 1.
5 million people, over one third of the population.
Towering above Weymouth is the Isle of Portland - although strictly speaking it's not an island at all.
The rock quarried here, Portland stone, is world famous.
St Paul's Cathedral owes its strength and colour to its enduring qualities.
Today it's still the stone that gives your high street bank more respectability than the burger bar next door.
Portland forms the eastern limit for that celebrated destination of geography field trips, Chesil Beach.
You can come here time and again and never cease to be amazed by the scale of it.
Right in the middle of the Jurassic Coast, Chesil Beach is one of the finest barrier beaches in the world, defending the Fleet lagoon and its migrating birds from the sea.
The wildlife is heavily protected now - but that's not always been the case.
During the Second World War, this is one of the places where the Dambusters' bouncing bomb was tested.
Now, though, its World Heritage status means that the 17 miles of Chesil Beach, along with the whole Jurassic Coast, is strictly managed.
But that doesn't mean it's preserved in aspic.
14 million people visit every year, and getting on for 170,000 live along it, many make a living out of the riches it has to offer.
Even if that means getting soaked! Hello, I'm Tony Gill and we're in Charmouth.
That's where I collect fossils.
I've been doing it for about 15 years.
The best place to go is the big mudflows that come out onto the beach.
Quite often you can see collections of wellies.
People have tried getting across, lost their wellies and had to have the coastguard pull them out of it.
What we're looking for is nodules.
They tend to be rounded in shape, sometimes flying saucer shape.
Quite often they will have squashed impressions of ammonites on top.
We'll break the thing open and see what it's got inside.
Not a lot! Some you win, some you lose! Again, nothing! I must have broken hundreds of thousands of rocks on the beach looking for fossils.
You never know what you're going to find - usually not very much.
The dream would be a dinosaur.
I want a dinosaur! The final stretch of the Jurassic Coast starts just beyond the fossil-hunting Mecca of Lyme Regis.
The red Triassic cliffs are an awe-inspiring sight, and mark my final miles to Exmouth.
As I near the end of the first leg of my journey, Dover's white cliffs seem a million miles from these red ones, but actually I've only done 330 miles and I've got another 11,370 to go! Reflecting on the first leg of this journey, it's hard not to be overwhelmed.
The unimaginable age of this coast is part of it, and so is the way that it's changing.
The struggle that's gone on to protect our freedom, and the relics that have been left behind, have all made me realise how much this frontline coast has protected us.
But it's also where we, as a nation, began to look outwards.
Just down there in Exmouth, local boy Walter Raleigh set sail on his voyages across the Atlantic which introduced the nation to the huge economic potential of empire.
We'll also be going west, to the tip of Land's End and back up the Bristol Channel.
It's the Wild West - a land of storms and wrecks of vanished villages and ancient myths.
Of summer surf .
.
and nightly toil on the sea.
But for many people, me included, the West Country means childhood holidays.
It's where I first saw the power of the ocean and learned about the resilience of this rocky Atlantic peninsula.
I'm not sure about this weather, though! For a free Discover Your Coast Pack call the Open University on 0870 900 77888 or go to bbc.
co.
uk/whereilive
The coast is where the story of an island nation, its history, its geography, and above all its people, is told most vividly.
This is life on the edge, the coast as you've never seen it before.
It's easy to think that the coast is merely where the country stops, where the land falls into the sea.
In fact, our coastline is at the very heart of our shared history, the source of so much national wealth, and where empire was born.
Many of us work here.
Even more of us come here to play.
But few of us have ever travelled its entire lengthuntil now.
This is a once-in-a-lifetime journey.
We'll be exploring the coast of England, Wales, Northern Ireland and Scotland, uncovering the treasures that have made us the island nation we are today.
But to fully appreciate the diversity of our coast, will take a diverse range of skills, so I'll be travelling with a small, dedicated team of experts.
Writer and historian Neil Oliver will explore the human stories behind the history.
Zoologist Miranda Krestovnikoff is our guide beneath the waves.
Anthropologist Alice Roberts will be grappling with the actual stuff that makes up our coastline.
Archaeologist Mark Horton is going to dig up the hidden histories along our familiar shores.
And me? Fantastic! Well, I just can't wait to get started.
An 11,700 mile adventure, this is the story of Coast.
The first leg of our journey takes us the 330 miles from Dover to Exmouth, a coastline pockmarked by a legacy of invasion and war.
This is Britain's frontline.
Many of our neighbours have had a crack at invading here.
One or two even succeeded.
Since Roman times, we've been fortifying this coast, building chains of linked defences, grand castles, Saxon shore forts, evolving and reinventing them as the enemy got stronger, but always looking nervously out to sea.
This is a Martello tower.
It's number three, just outside Folkestone.
Number one Martello tower is over there, and nestling down in the hollow is number two.
And stretching away along the south coast in that direction, another 71! All 74 towers were built in the early 1800s at a time when Napoleon had overrun most of Europe and saw no reason why Britain should be left out of his grand design.
Oh, it's rather beautiful.
There's not a straight edge to be seen on the ceilings or the walls, it's a room entirely full of curves.
And look how thick the walls are.
Each of these towers was built from half a million bricks, and they might look round, but actually it's elliptical, built thicker on the seaward side to withstand the cannon fire of an attacking French navy.
The building of 74 towers was a hugely ambitious engineering project, but ultimately they were never put to the test.
In 1805 Napoleon's seemingly unstoppable march through Europe was halted when he was beaten by Admiral Lord Nelson at Trafalgar.
The final nail in the coffin came ten years later at Waterloo.
Napoleon was a spent force.
For the next 100 years, war, at least as far the British were concerned, was something that happened a long way away, never on our own shores.
That long spell of peace at home came to an abrupt end with the outbreak of the First World War.
The German aircraft that bombed London in 1917 were primitive, but they proved that warfare had taken to the skies.
When the war was over, military strategists had to face an alarming truth.
The waters around our shores, dominated for over 500 years by the navy, could now just be flown over.
In future, wars would be won or lost from the air.
The success of our defence would depend on early warning of attack.
And before the advent of radar, the best chance we had of getting that early warning was one of these, monolithic upturned concrete soap dishes.
Known as sound mirrors, these top-secret constructions, built between the wars, were designed as giant ears to listen out for approaching enemy aircraft.
Most of them have been demolished, vandalised or have simply rotted away, but remarkably this one just outside Folkestone is still standing.
And just 18 miles further down the coast, at Denge near Dungeness, there are three more sound mirrors.
Considering they were abandoned more than 70 years ago, they're in remarkable condition.
It's hard to believe that these long forgotten relics of war played a vital role in the defence of the United Kingdom.
Great to meet you.
'Richard Scarth has dedicated 20 years of his life to the study of the mirrors.
' Richard, they're incredible! The sound mirrors were the life's work of one man, Dr William Tucker.
Richard, by the time Tucker came here, he'd been working on sound-detection equipment for 20 years.
He had, and the results of their work was this magnificent structure here, the biggest sound mirror of all.
This is a monument to his life's work.
Yes, it is, yes.
It is absolutely fantastic.
It's enormous.
In their day these mirrors were the cutting edge of military hardware.
70 years on, they lie abandoned and the secrets of how they work forgotten.
With the help of the National Physical Laboratory and the Open University, we're going to unravel their mysteries and get them working again.
Very little technical information has survived, so our scientists are going to have to work from scratch.
And their first discovery is that the mirrors are much more complicated than they appear.
OK, so it's ready to go, then.
Yeah, cos that's as far as we're going up.
In the 1930s, as Tucker's team struggled to perfect the sound mirrors, tension was rising across Europe.
And in Britain the government began to assess the country's readiness for war.
As part of those exercises, aircraft were flown towards the sound mirrors to assess their early-warning capabilities.
We've got a Tiger Moth standing by to do the same thing, but before it can take to the air, we've got to discover how the mirrors actually work.
A little bit more, try a little bit more.
By setting up two microphones - a red one listening to the mirror and a control microphone marked with blue, well away from the mirror - our scientists hope to reveal the sound mirrors' secrets.
Well, what we're using is a single tone, and so what that shows up on this graph is a single peak, and you can see this single peak here.
A very dramatic spike.
On the top graph Which is the red microphone.
At the sound-mirror focus, you can see that we've got a level which is up around 70-80 decibels, in fact.
On the blue graph at the bottom That's the microphone standing in the open.
Yep, you can see the level's much lower, down at about 60 decibels.
So the sound-mirror microphone is picking up much more sound.
It's amplifying it by as much as 15 decibels.
So this is exactly what Tucker's physicists would have been doing all those years ago.
Exactly.
Our first eureka moment.
The sound mirror makes the tone almost four times louder.
In the simplest case, an aeroplane could be coming in, sound waves coming from that aeroplane are going to hit the mirror at different points.
And where those reflected rays meet is what we call the focal point, and you'll get an increase in the sound level at that point.
But if say, for example, the aeroplane was off axes, sound travelling from that is going to bounce off the mirror.
But this time the angles would have changed, the focal point has now moved down to here.
If you simply move your microphone, you can get not only an early warning that a plane's coming in, but also the direction.
Which is the essence of early warning.
Absolutely.
That's got enough water out, we can now see how the mechanism worked, can't we? Yes, and you've got to imagine that underneath here was an operating room, and there's a man sitting in there who's got control of this apparatus, which is designed to move a trumpet which was on the end of that arm over the focal area of the mirror.
The mirror's designed to focus sounds just a few feet in front of it, and so the collector went round at that plane and picked up the sounds, hopefully, of a distant aero-engine.
And when he listened in his stethoscopes, when he got to the place where it was the loudest, that was the direction the aircraft was coming.
Of course the idea was that there would be several of these mirrors up and down the coast and they could work together to a control centre, and they'd get cross bearings, which would give them more accuracy.
At the heart of this larger network of mirrors was Dr Tucker's 200 ft wall.
Armed with the understanding we've gained from our experiments at the smaller mirror, our scientists are now ready to use Tucker's wall for our own early-warning test.
Our Tiger Moth will head out to sea, then turn back and approach the mirror along its axis, which we've marked with a white sheet.
Flying at 500ft and 90mph, this mimics one of the government tests from the 1930s.
I'm gonna put these headphones on, which are wired up to the red microphone in front of the mirrors, so if Tucker's wall works, I'm going to hear the plane first.
Yes.
The piston-engined Tiger Moth of the 1930s sounds exactly like the planes that Tucker's men would have been listening out for.
The tension's really unbearable, just waiting.
Complete silence.
Headphones are silent I can't see anything yet.
ENGINE HUMS I'm getting something! I can hear it! And some spikes! I can't hear a thing without them on.
Nothing on the blue traces.
Blue trace This definitely isthe Tiger Moth, there's its fingerprint.
Fantastic! ENGINE HUMS Now I can hear it really clearly.
Yeah, here he comes.
Really loud now.
There it is! Right above us at last! Tucker's machine beat the human ear by a long way.
That was fantastic.
70 years on, it still works.
So we got nearly 40 seconds or about a one mile advance warning.
Not bad for a 70-year-old piece of concrete, but nowhere near Tucker's best-ever results of over 20 miles.
But in 1933, while Dr Tucker and his team were toasting their success, other scientists were measuring a BBC radio signal as it bounced off a Hayford bomber.
After only five months in development, this discovery, the earliest form of radar, was was detecting planes over 40 miles away, twice the distance that the sound mirrors had ever achieved.
It was all over for Dr Tucker's acoustic detection system.
By 1937, the sound mirrors had been abandoned.
Well, what became of Dr Tucker? For some reason that nobody seems to be able to explain, he was more or less forcibly made to retire, and one of the last things he was asked to do was to destroy the mirrors by blowing them up, but thank goodness he didn't obey his orders.
Dr Tucker's retirement may have been the end for the sound mirrors, but nevertheless they were to have a profound effect on the course of the Second World War.
The reporting structure that Tucker developed for the mirrors was copied by the radar team and led directly to their success in the Battle of Britain.
The 7.
45 from Hastings to London.
Not an obvious choice for a coastal journey.
But something rather interesting has happened along this stretch of the coast.
It's easy to think of our coast as unchanging.
In fact, it's constantly in flux.
We are now approaching Pevensey Bay.
Would customers please note? Erosion is eating away at much of our famous landscape.
And yet here in Pevensey Bay, different forces have been at work.
Since William the Conqueror landed almost 1,000 years ago, the shoreline has changed beyond recognition.
Rather than eroding, it's been growing.
As much as a mile-and-a-half has been added, reclaimed from the sea.
Land reclamation, or "inning", has been going on here since the 13th century, when the local church authorities would pay to have the land drained and turned over to agriculture.
But just beyond Eastbourne, where the commuters and I part company, is Beachy Head, the flipside of coastal change.
At 163 metres above sea level, the cliffs at Beachy Head are the highest chalk sea cliffs in the United Kingdom.
The question is, as they say in the soap powder ads, how do they stay so white? The unhappy answer - erosion.
The cliffs barely have time to get dirty before the wind and waves strip them away.
Up to a metre is lost every year.
In 1999, the Belle Tout lighthouse made headline news when the owners paid nearly ï¿¡200,000 to have it moved back from the cliff edge to prevent it falling into the sea.
At the current rate of erosion, it's a procedure they'll have to repeat in 2016.
And again in 2033, 2050, 2067, 2084 20 miles further round the coast is Brighton, a resort with a long established reputation for hedonism.
For centuries, it's played host to an invasion of Londoners who want a bit of sin by the sea.
Or in it, for that matter.
Its long beach, that stretches from Brighton to Selsey Bill, it's a playground for holidaymakers.
But beyond the candyfloss and deckchairs, there's another world - a world beneath the waves that most of us never get to see.
This journey is not just going to take us along the coast, but into the seas around our islands, to reveal the extraordinary diversity of our marine wildlife .
.
a subject that zoologist, Miranda Krestovnikoff, has been studying all her working life.
I've dived all over the world, but it's easy to forget there are some stunning wildlife dives much closer to home.
But when two local divers, Robert Walker and Paul Parsons, told me there was a good chance of photographing cuttlefish just offshore here, I was a bit sceptical.
So are we expecting to see activity like this if we dive today, or is this unique? I think we will find cuttles.
We may not get this activity, because everything has to be just right, but we should be able to find cuttlefish, hopefully mating.
All this equipment and all this effort, I really hope it's worth it and there are cuttlefish down there.
The vis may not be that good but once you get your eye in, there's loads to see down here.
Here's a tube worm.
This feeds by just picking up whatever's floating past in the current.
If I just reach out and touch it with my finger, there you go.
It's retracted its tentacles.
We're only a few metres out and a few metres deep.
There's so much marine life here.
This little dragon-looking creature is a pipefish.
They look a bit like sea horses, they're related to sea horses.
Oh look! There's a cuttlefish.
Exactly what we wanted to see.
They're such exotic looking creatures.
You'd never imagine to find something like this right here in British waters.
It's very big.
A couple of feet long.
They look sort of alien.
A really, really unusual shape, with those big eyes and this floating skirt.
Really odd-looking creatures.
Cuttlefish are in the same family as squid and octopus.
Sometimes known as the chameleon of the sea, they can change their body colour and patterning to mesmerise their prey.
I've just realised there's a change, and up there there's two tentacles, and they're going a darker colour.
It's obviously feeling a little bit threatened.
That's its threat posture.
Off he goes.
Gosh, what's he got? Goodness me, he's just grabbed a crab! That's amazing.
Don't think I've seen that before! Cuttlefish have a sharp parrot-like beak and a venomous bite, which will make short work of this crab.
As the sea warms in spring, cuttlefish invade these shallow waters to mate and lay their eggs.
This part of the south coast is a real hot spot for them.
Male cuttlefish dazzle the smaller females with their striped patterns and flowing tentacles.
They mate head to head, with tentacles entwined.
After mating, the male cuttlefish guards his female as she deposits her eggs, dyed black with ink to deter predators.
This cuttlefish invasion lasts all summer, but with the water cooler, and their life cycle complete, both males and females die, leaving their bones to be washed up on the beach.
Truly amazing.
Diving this close to the shore, and seeing these weird, weird creatures.
That's a pretty incredible dive.
We're almost halfway through the first leg of our journey to Exmouth.
About 130 miles from Dover is the city of Portsmouth, the place with centuries of maritime history, a fair proportion of which is connected directly or indirectly with the Royal Navy, down there.
Her Majesty's naval base, Portsmouth, currently harbours two thirds of the Navy's surface fleet.
But the city's proud naval tradition goes back nearly 1,000 years, with many decisive military campaigns being launched from here.
The fleet's biggest engagement of recent years was in 1982.
On 5th April, the first ship set sail from Portsmouth on the 8,000 mile journey to the Falkland Islands.
The question is, why here? Why was Portsmouth chosen above other ports on the south coast to be home of the Royal Navy? Archaeologist Mark Horton is in the Historic Dockyard to find the answer.
Morning.
Morning.
Shall we go for a trip? Yes, climb aboard.
My guide, Roy Rolfe, started off by explaining how the geography here works to make this place an ideal port.
Crucially, the huge expanse of water in Portsmouth harbour is only accessible through a small entrance.
Right in the entrance now, you can see it's very narrow.
And presumably defensible because it is so narrow.
That's right, yes.
We're now actually out into the entrance channel to Portsmouth Harbour.
And on the shore of the Isle of Wight.
The Isle of Wight is one of the main reasons why this is such a good harbour.
So that's as a sort of protection - despite the fact we can see the wind coming in, it's quite sheltered.
And it also means the harbour is always usable.
You don't get the sort of weather you could get at Dover sometimes, by the breakwater, where it's something of a lottery to get in and out in very bad weather.
The harbour at Portsmouth has a lot to recommend it, but in many ways its trump card has nothing to do with its physical geography.
And everything to do with politics.
For much of our history, England was at war with her continental neighbours.
First the French, then the Spanish, and then the Dutch.
In those battles, it was considered important to have a harbour as close as possible to the enemy.
For the Spanish wars, that meant Plymouth.
For fighting the Dutch, Chatham in Kent was best.
But it was the French wars that were begun by Henry VIII that really made this place important.
Henry created the Royal Navy in 1525, and decreed that Portsmouth should be its home.
Through fighting the French seven times in 290 years, Portsmouth grew from 1,000 people in 1545 to over 30,000 in 1800.
Now the docks were home to 684 ships, and were the largest industrial complex in the world.
But things for Portsmouth were about to change again.
Just listen to that wind to the rigging.
The Victory, where Nelson defeated the French 200 years ago at the Battle of Trafalgar.
But ironically, it was that victory against the French that changed the role of Portsmouth for ever.
From the base where we fought the French, to the place where we patrolled the world and fulfilled our imperial ambitions.
For the next 200 years, Portsmouth's growth was driven more by technological innovation than military need.
The move from sail to steam in the 19th century saw the biggest expansion.
It's the sea just the other side of those somewhat rusty gates.
This is the number six dry dock, one of around 20 here.
Portsmouth was not just the centre of the naval operations, but also an important dockyard, where ships could be built, and comfortably repaired.
As the ships got larger and larger, so the dry docks themselves had to get bigger and bigger to keep pace with technological change.
If the 19th century saw Portsmouth grow with every new technology of war, the 20th century saw the benefit during two world wars.
In the 21st century, warfare continues to change.
So what is the future for our oldest naval base? For the surface navy, the escorts and the aircraft carriers, this is where it's all at, yes.
And does it still work as a harbour? Is it suitable for the modern navy? Oh, very suitable.
There's a large investment programme going on to make sure it continues to be suitable, continues to evolve to meet modern requirements.
Portsmouth is here because of medieval monarchs, Henry VIII and the French.
I think the reason he chose it is because France was the enemy.
Today that is not the case.
Do you think in 500 years' time, there will be a base here at Portsmouth? As long as we've got a navy, it will still be here.
Leaving Portsmouth behind, we're continuing west.
18 miles further round is this coast's most important commercial port - Southampton.
Massive liners like Queen Mary II make regular trips to New York from here.
But more infamously, in April 1912, the Titanic's maiden and only voyage began from this port.
Southampton is also the starting point of historian Neil Oliver's flight to Alderney, the third largest of the Channel Islands and the place on our shores which bears the scars of invasion more vividly than anywhere else.
The British Isles comprise over 6,000 islands, many of which we'll visit on this journey.
But unlike the Scottish islands, or say, the Isle of Wight, the Channel Islands are technically not part of the United Kingdom.
Even so, they come under the protection of the British crown.
65 years ago, that protection was tested to breaking point.
During the Second World War, the Channel Islands were occupied by German forces.
Alderney became home to four forced labour camps and nearly 7,000 slave labourers.
Those are the bare facts.
What they don't tell you, though, is what the slave labourers were really doing on Alderney, and what their day-to-day existence was actually like.
That's it, I'm through.
No passport control, no customs, because I'm still in Britain.
By 1940, with the German forces in control of Western Europe, the first invasion of British soil in nearly 900 years looked inevitable.
7.
5 miles from the French coast, the people of Alderney were going to be the first Britons to be overrun.
CHURCHILL: We shall fight on the beaches, we shall fight on the landing grounds.
We shall fight in the fields and in the streets Of course, there were a few beaches that Britain wasn't going to be fighting on.
After the fall of France, the Channel Islands were in the front line and the British Army decided that the best move was to evacuate the islands and leave their fate in the lap of the gods.
So this is where it took place, then, the evacuation? 'Buster Hammond was among the first to be given the order to evacuate.
' Can you describe what that was like? I can't imagine the thought of leaving everything I've known.
I mean, when the door of the house that you're living in is opened - you never locked them anyway - and a man's voice shouts up the stairs "The boats are in, "you've got two hours to leave, "to board, one suitcase each".
I mean, what do you go to get actually in cases like that? We were more concerned about the cat.
When you were all down here waiting to get on the boats, what was the atmosphere like? No panic, no panic.
We just waited our turn, got on board the boats, just as simple as that.
I dare say there was a few tears here and there, naturally.
I mean some of the people had never been off the island.
The islanders were taken to England, uncertain when, or even if, they would ever see Alderney again.
Once that last ship had sailed, the island of Alderney was abandoned, and here, St Anne's, was a deserted ghost town.
Clothes left hanging in wardrobes, fires going cold in the hearth.
The whole place was at the mercy of whoever was coming.
Within days of the evacuation, Luftwaffe reconnaissance planes were circling the island like vultures.
Then on 2nd July, the Nazis landed on Alderney soil for the very first time.
The Germans had invaded an empty island.
It wasn't long before they began to implement their plans for Alderney.
It was one of the principal Channel Islands, and effectively they were providing offshore gun platforms for the French from the mainland of France.
In 1941, Hitler ordered the construction of huge bunkers like this, as well as gun emplacements and fortifications all over the island.
This tiny little door is the only way in.
It is a pretty impressive structure.
Look at the depth of the walls.
Two metres thick.
Concrete, reinforced.
There we are.
Turn through 90 degrees here.
Lead on.
On the right we've got an entrance defence position.
And this corridor then leads forward.
Daylight.
You get an idea of the panorama.
That is just brilliant, isn't it? What a view.
I'm beginning to realise what the concentration camps must have been for.
The scale of construction here is awesome.
They were labour camps for the building of these bunkers.
The masterminds behind this scheme were infamous German construction force, Organisation Todt.
The Organisation Todt cut their teeth on the building of the German autobahn system and the fortifications of the west wall in Germany.
So that by the time they came to the occupied countries of Europe, they were experienced in building this type of fortification.
So is this literally the book that you could work from to build your defensive position? Yes, absolutely.
It's the pocketbook carried by the engineers when they came to the site.
I love these artists' impressions of what your finished bunker is going to look like once the grass is back.
It's chilling how clinical these plans are.
Because however sanitised they look, you can never forget they were built by slaves.
The forced labourers who worked here for Organisation Todt were accommodated in four camps, all of them named after German North Sea islands.
There was Heligoland, Borkum, Sylt and right down there, Norderney.
Camp Norderney held over 1,500 prisoners from all over occupied Europe.
They were kept in filthy wooden shacks.
Today nothing remains - no clue to the story of what happened here.
One of the last surviving prisoners is 82 year-old Monsieur David Trat, a French Jew who was only brought here and spared the death camps of Auschwitz because his wife was a Christian.
HE SPEAKS FRENCH How were you treated by the guards here? "We were beaten with everything they could lay their hands on - "with sticks, spades "There were many men among us over 70 years of age "Hard physical work "We were accused of laziness, but mostly we were beaten out of hatred.
" How did you survive? Many would never see their families again.
No-one knows exactly how many died in the labour camps on Alderney.
The official figure is 437.
But many believe the death toll was much, much higher.
The surviving slave workers were finally moved from the island to camps on mainland Europe on 7th May 1944.
One month later, the liberation of Europe began, but the Channel Islands remained under increasingly desperate German occupation for a further year.
Finally, in May 1945, the Germans surrendered.
Buster Hammond was one of the first islanders to return home.
It was so exciting, and the thing that struck us most was the number of buildings that had been put up by the Germans, and when we came inside the breakwater, one of our local men, a Salvationist, put the trumpet up and played "Home Sweet Home".
It was just The sheer magic of being five and a half years late to come back.
For Monsieur Trat, coming back to Alderney is a more difficult experience.
This is the mouth of Poole Harbour, the second largest natural harbour in the world after Sydney.
With its warm micro-climate and spectacular beaches, the village of Sandbanks at the harbour mouth has the distinction of having the 4th highest land values on Earth, beaten only by New York, Tokyo and London.
A four-bedroomed house on this tiny spit of land goes for as much as ï¿¡2.
5 million.
The chain ferry takes about five minutes to cross between Sandbanks and Studland on the other side.
The alternative is a 26-mile drive around the bay.
And more than a million people make use of it every year, some of them to take advantage of the rather special freedoms available on Studland Beach.
My name's Keith Basham.
I live in Bournemouth.
I come across here to Studland because it's such a fabulous place to be, very relaxing and the views and the scenery here are unbelievable.
I think a naturist is somebody who enjoys the freedom and the relaxation of being naked.
It's not a sexual thing - it's purely a sensitive and sensual feeling.
We have an area devoted to naturists, and obviously the rest of the beach is for non-naturists.
It would be nice in a really hot climate where there's no problem with cold nights etc etc, but enjoying naturism on a beach - I don't think I could enjoy anything more special than that.
I do have friends that are not naturists, but I will be undressed and they won't.
They accept me as a naturist and I accept them as what we call a textile.
West of Studland Beach, the nature of this coast changes in the most dramatic way.
These chalk stacks, known as Old Harry Rocks, mark the beginning of the last third of our journey, and the start of 95 miles of cliffs and beaches known as the Jurassic Coast.
The history laid bare here belongs to the age of the dinosaurs at a time when this land mass lay thousands of miles to the south on the equator.
For anyone interested in the evolution of our planet, this is the best place in the UK.
Like the millions of visitors who come here every year, anthropologist Alice Roberts has a special place in her heart for this stretch of our coast.
The extraordinary thing about this length of coastline is that it spans nearly 200 million years of Earth's history - that's three geological time periods.
And for that reason, in 2001, the United Nations designated the Jurassic Coast a World Heritage Site, alongside iconic places like the Great Barrier Reef and the Grand Canyon.
In fact, though, the Jurassic Coast is a confusing name because, along its 95-mile length, there are younger Cretaceous and older Triassic rocks to be seen.
The Cretaceous rocks at the eastern end were formed at the time some of the largest dinosaurs roamed the Earth.
Further along, and further back in time, are the fossil-rich Jurassic rocks, created as the Earth saw an explosion of marine life.
And finally, at the far western end, are the very oldest rocks of this heritage coast.
The striking red Triassic cliffs were formed up to 250 million years ago.
What's unique about this area is that these three geological periods, which together make up the Mesozoic era, are laid out next to one another.
But the process that's created them takes some explaining.
Lovely! Thank you.
I've got three slices of cake in front of me.
This first one is going to be the earliest rocks we find along the coastline, the Triassic rocks laid down between 200 and 250 million years ago.
They're red sandstone rocks, laid down in the middle of a great arid desert.
The next layer is Jurassic.
Here we have a story of sea levels rising and falling and marine sediments being deposited - limestone, clays, that sort of thing.
Lots and lots of fossils in this segment.
This is between 200 and 140 million years ago.
Finally we have the most recent rocks, the Cretaceous rocks.
These were laid down in swampy environments.
Those represent between 140 and 65 million years ago.
If that was the end of the story, we would be standing up here and we wouldn't be able to see the Jurassic or Triassic rocks underneath.
In fact, what happened during the Cretaceous period was that the whole thing sank down in the east, so that we end up with in fact all of these layers pointing up to the west end.
And then it has eroded, so if I represent the erosion by cutting through the cake at an angle like that Then what we've got is the land surface of today.
We start in the east at Old Harry Rocks, and we walk through cliffs that are Cretaceous, then suddenly we find ourselves walking along Jurassic cliffs, and finally into the oldest rocks, Triassic rocks, until we get all the way to Exmouth at the end of this prehistoric walk along the coast.
And it is quite delicious! Here at Lulworth Cove, deep in the middle layer of the cake, the Jurassic rocks tower above the beach.
For nearly 200 years, they have been attracting visitors on the hunt for the fossils they contain.
But there's actually something hidden in these ancient rocks that is much harder to find.
Just to the west of Lulworth Cove is Stair Hole.
There I met Dr Andrew Hindle, a geologist who has been searching for the liquid remains of fossilised sea creatures - oil to you and me - for over 22 years.
It's not just an academic interest.
You're actively prospecting for oil here, aren't you? Yes, just like Sherlock Holmes, just getting all the information.
So you're looking at structures and trying to predict where the oil will be under the surface.
Yeah.
A colleague and I set up an oil company to look.
We think there are several hundred millions of barrels still here.
Several hundred millions? Underground in Dorset? Very close to where we're sitting.
That's amazing! Hundreds of millions of barrels of oil? With that number ringing in my ears, Andrew hit me with another surprise.
Just a few miles west of Lulworth Cove is an area known as Burning Cliff - for very logical reasons.
Apparently, one of the strata in the rock face has been known to catch fire spontaneously.
Which layer was it that was burning? It was these dark coloured shales you see down the base of the cliff.
It was this area here, which is largely landslip now and covered up.
That was the bit that was on fire.
But it wasn't the vegetation? It was the actual rock? That's right.
This Kimmeridge clay here is about 80% organic matter - fossilised plants and animals.
Algae and plankton that's been laid down at the bottom of the sea? That's right, and preserved.
They're very organic-rich.
That gives you the fuel source, if you like.
It's really strange.
We are actually looking at a section through a fossil fuel.
That's what a fossil fuel is.
That's absolutely right, yeah.
The Kimmeridge oil shale at Burning Cliff is named after a place just along the coast called, unsurprisingly, Kimmeridge Bay.
There we met Paul Farramond, a geochemist, who was going to show me on a smaller scale, what the Burning Cliff must have been like.
The oil shale are these bands here, which, where they're orange, you can see them higher up in the cliff as well.
Just break a bit off.
There we go.
Is that a big enough piece? Yeah, that'll be fine.
I don't believe it's going to set on fire - it's a piece of rock! I think you'll find it will.
It's just beginning to catch there.
As you see, lots of smoke comes off it.
It's definitely on fire! But, as you can see, it goes out quite easily.
And it stinks! It really is bad, yeah.
That's right.
You can see the oil coming off the surface of the Kimmeridge shale.
That's oil as we understand oil to be? Yes, absolutely.
The Kimmeridge shale was the source rock of most of the oil in the North Sea.
When you say source rock, you mean the same layer as we have here? Absolutely, yeah.
And that's the real magic of Kimmeridge oil shale.
This rock is the reason we have North Sea oil.
The same strata that are visible on the south coast are buried 3? kilometres deep, under the oil wells off the north east of Scotland.
Over millions of years at the high temperatures and pressures deep under the seabed, the oil shale produces oil.
In place of 10 million years at 100 degrees centigrade, we can do 30 seconds at 500 degrees centigrade and drive some oil off in the test tube.
If you wanna hold that in the tongs You can see it's not actually burning, it's just driving the oil off.
There you can see all that brown, looks like smoke.
It's actually just oil being distilled off the rock.
You can see droplets of oil around the side of the tube.
The brown stuff? That's actually oil that has been driven off.
Wow! This stinks as well! Yeah.
It's fascinating to see oil being produced in front of your eyes like that, but remember, Andrew is still looking in this area for the naturally occurring stuff.
30 years ago his predecessors were looking for the same thing, and just above the beach at Kimmeridge they struck lucky.
It's the last thing you expect to find in the middle of rural Dorset.
That's right.
Is it really just an experimental thing or is it producing on a commercial scale? It's very much a commercial scale.
They're producing 100 barrels of oil a day.
At current oil prices about 4,500 a day, so quite a significant income.
The find at Kimmeridge led to another near Poole Harbour.
Together these wells pump more than 2 million worth of oil out of the ground every day.
But in each of the last six years Wytch Farm has produced less oil than the year before, so for prospectors like Andrew the race is really on to get that next big find.
Spectacular geology isn't the only thing that the Jurassic Coast has to offer.
It is also home to several of our better-known seaside resorts, the biggest being Weymouth.
It's now a pretty Georgian town.
But it has a dark past.
It was here, far from the battle-hardened eastern end of our frontline, that the last truly devastating invasion took place - an invasion that resulted in the death of a greater proportion of our population than any war in history.
But it wasn't an army that arrived in June 1348.
It was the Black Death.
It's customary to blame its introduction on the rat.
But actually the carrier was a sailor recently arrived in this port from France.
By August 1348, two months after its arrival, the plague had reached Bristol.
A month after that, London and on into East Anglia and the Midlands.
In under a year, it overran Wales, then Ireland, then Scotland.
In 18 months, the Black Death killed 1.
5 million people, over one third of the population.
Towering above Weymouth is the Isle of Portland - although strictly speaking it's not an island at all.
The rock quarried here, Portland stone, is world famous.
St Paul's Cathedral owes its strength and colour to its enduring qualities.
Today it's still the stone that gives your high street bank more respectability than the burger bar next door.
Portland forms the eastern limit for that celebrated destination of geography field trips, Chesil Beach.
You can come here time and again and never cease to be amazed by the scale of it.
Right in the middle of the Jurassic Coast, Chesil Beach is one of the finest barrier beaches in the world, defending the Fleet lagoon and its migrating birds from the sea.
The wildlife is heavily protected now - but that's not always been the case.
During the Second World War, this is one of the places where the Dambusters' bouncing bomb was tested.
Now, though, its World Heritage status means that the 17 miles of Chesil Beach, along with the whole Jurassic Coast, is strictly managed.
But that doesn't mean it's preserved in aspic.
14 million people visit every year, and getting on for 170,000 live along it, many make a living out of the riches it has to offer.
Even if that means getting soaked! Hello, I'm Tony Gill and we're in Charmouth.
That's where I collect fossils.
I've been doing it for about 15 years.
The best place to go is the big mudflows that come out onto the beach.
Quite often you can see collections of wellies.
People have tried getting across, lost their wellies and had to have the coastguard pull them out of it.
What we're looking for is nodules.
They tend to be rounded in shape, sometimes flying saucer shape.
Quite often they will have squashed impressions of ammonites on top.
We'll break the thing open and see what it's got inside.
Not a lot! Some you win, some you lose! Again, nothing! I must have broken hundreds of thousands of rocks on the beach looking for fossils.
You never know what you're going to find - usually not very much.
The dream would be a dinosaur.
I want a dinosaur! The final stretch of the Jurassic Coast starts just beyond the fossil-hunting Mecca of Lyme Regis.
The red Triassic cliffs are an awe-inspiring sight, and mark my final miles to Exmouth.
As I near the end of the first leg of my journey, Dover's white cliffs seem a million miles from these red ones, but actually I've only done 330 miles and I've got another 11,370 to go! Reflecting on the first leg of this journey, it's hard not to be overwhelmed.
The unimaginable age of this coast is part of it, and so is the way that it's changing.
The struggle that's gone on to protect our freedom, and the relics that have been left behind, have all made me realise how much this frontline coast has protected us.
But it's also where we, as a nation, began to look outwards.
Just down there in Exmouth, local boy Walter Raleigh set sail on his voyages across the Atlantic which introduced the nation to the huge economic potential of empire.
We'll also be going west, to the tip of Land's End and back up the Bristol Channel.
It's the Wild West - a land of storms and wrecks of vanished villages and ancient myths.
Of summer surf .
.
and nightly toil on the sea.
But for many people, me included, the West Country means childhood holidays.
It's where I first saw the power of the ocean and learned about the resilience of this rocky Atlantic peninsula.
I'm not sure about this weather, though! For a free Discover Your Coast Pack call the Open University on 0870 900 77888 or go to bbc.
co.
uk/whereilive