-Escape with us on a magical voyage through the green heart of southwest France.

-It reminds me very much of England with sunshine, which is a definite bonus.

-We're traveling a once vital highway past fairy tale castles which hide a turbulent past.

-The famous Battle of Castillon, the English army suffered its biggest defeat.

-But now this is a tranquil playground.

-I'm very happy here.

-We'll be guided by those who live, work, and play in its handsome towns... -Welcome to the gardens.

-...and deep beneath the earth.

-We are 103 meter underground.

-As we hunt for culinary treasure fed by its waters... -[ Speaks native language ] -...and have a drink or two.

-We'll be drunk by noon.

[ Laughs ] -These shallow waters once hummed with commotion, but today, they are a haven of peace.

-The sunrise are beautiful.

Just beautiful.

-Making this one of the most scenic river journeys in the world -- The river Dordogne in France.

♪♪ ♪♪ Rising as a small stream in France's Massif Central, the Dordogne links these volcanic highlands to the great city of Bordeaux and the Wild Atlantic, more than 460 kilometers away.

Our first taste of the waters is at the western edge of these uplands.

-It reminds me very much of England because it's very green with sunshine, which is a definite bonus.

-A decade ago, Englishman David Freeman gave up life in London's commuter belt to work here as a bus driver on school days and a river tour guide on holidays.

On board this traditional flat bottomed barge called a gabarre.

-Now the Dordogne River in this region, they called it the White Lady.

And it was a very, um, kind of respected thing because it was the only way of transporting a lot of goods the length of France.

Gabarres are uniquely designed to handle the challenging trip down river, and were once the workhorse of the Dordogne.

-But you've got to bear in mind that back in those days, the river wasn't as calm as it is here, because further down river is a dam, so the river level has been raised considerably.

And, um, back in the day it would have been a lot lower and a lot fiercer.

-The jumping off point for many gabarres was the prosperous river port of Argentant.

Holiday cruise would stop here to load roughly-made gabarres with timber, stone, and grain for the trip down river, singing as they go.

-[ Singing in native language ] -They would need good cheer.

The journey could take weeks or more, with dozens of dangerous rapids to navigate.

As for the boat trip back, well, there wasn't one.

-The gabarres themselves were very kind of rudimentary the way they were built, because ultimately they were only built for one journey.

And once they had arrived at their destination, they would have been broken up because they didn't have sails.

And it was absolutely no way of getting the gabarres back up upriver.

They would have unloaded it and then sold it locally as firewood.

-If they made enough money, a crew could buy a ride home on a horse-drawn wagon.

Most were not so lucky.

We, however, are traveling in style as we follow the historic route of the gabarres, taking in the stunning natural landscapes of the Dordogne Valley before passing the picturesque medieval village of La Roque-Gageac and the imposing fortress of the Chateau of Castlenaud.

We'll hunt for truffles in the hills of the Perigord and take in the view from the Panoramic Gardens of Limeuil.

We visit the town of Bergerac and stop for a drink in the famous vineyards of Saint-Emilion.

Before boarding a luxury liner to carry us towards the sea, where we'll explore the ornate Cordouan Lighthouse.

As we follow the river southwest, we enter the heart of the great Dordogne Valley.

Around 50 kilometers from Argentant, where we started, limestone cliffs tower above small villages.

For local canoeists Sally Fabre and Patrick Lakatos, it's the ideal spot for a paddle.

-We're going to go right up the river because there are a lot of new things to see.

♪♪ -[ Speaks in native language ] -Patrick was born in this region, but Sally relocated here from her native England about 30 years ago.

-I first arrived as a French assistant in a -- in a local school where my husband worked as well, and we think there's a lot of space and nature reigns.

I'm very happy here.

-Patrick guides friends and tourists along this scenic stretch of the river, and Sally leads canoe trips herself for disadvantaged children, most of whom have never seen the wild beauty of a place like this.

-They come from all over France.

A lot of them come from the cities.

Those are young who've only lived in institutions.

So the idea of coming into a home is really different.

And they learn how to ride bikes and just walk in the forest and discover, and there's a huge transformation.

They love it.

-[ Speaks native language ] -The limestone that forms this land was laid down in Jurassic times, when dinosaurs walked the earth.

But what truly shapes the landscape is water, carving this valley over millions of years.

It's also mined many caves deep inside the hills, not far away along a different river is less so.

Home to a 20,000-year-old prehistoric art gallery.

But closer to hand, there are caves where nature is the artist, and the canvas is unlike anything on the face of the earth.

-The story is that the devil created the -- the chasm, and then that he was hiding at the bottom of it.

-We're deep inside the wild Dordogne Valley, where the river cuts through miles of ancient woodland dotted with occasional pasture.

Its waters are swelled by dozens of small tributaries, but not all of them can be found at ground level.

This is the entrance to the caves of Padirac, an immense hole 100 feet in diameter, leading to a vast system of underground caverns.

-The water managed to come through the cracks and broke down the limestone and created here a big chamber.

And then because of the erosion, a roof fell off, and now it's an open chasm.

-For centuries, this was a place of fear and superstition.

-The story is that the devil created the chasm, and then that he was, um, hiding at the bottom of it.

So people didn't really go down the chasm in fear of meeting him.

-In 1889, a Parisian lawyer and amateur explorer named Edourad-Alfred Martel dared to face down the devil and the 75 meter drop to the bottom.

He discovered a secret tributary of the Dordogne, running for 20 kilometers through a unique subterranean world.

-We are on the underground river of Padirac, 103 meters underground.

-Some would have jealously guarded a find like this, Martel decided to share it.

-He wanted people to discover how gorgeous it is.

So the place opened to the public in 1899, so 10 years after the discovery.

And it's been open since.

-Visitors from that day on have been astonished by this river and what lies beyond.

This gigantic cavern and everything inside it was created by nothing more than rain.

Rainwater is naturally acidic, and as each drop drips through the rock, a chemical reaction dissolves just a few grains.

Then a few more are dissolved with the next drop and the next, which over eons, carve a chamber higher than London's St. Paul's Cathedral.

-It is my favorite place here because the color of the lake is -- is really blue and the stalagmite is really special.

So we don't have a lot of stalagmite here because there is the river at the bottom of the gallery, but we have this giant stalagmite and it's the only one like this.

-We're now more than 1,000 meters inside the earth, and this is as far as most visitors can go.

But for those with specialist skills, it's just the beginning.

Experienced cavers have mapped out a limestone labyrinth stretching almost 40 kilometers.

As for the river, a series of expeditions have traced it from its underground source... to this tranquil pool on the banks of the Dordogne itself.

Even after a century of exploration, parts of the network remain unmapped, and cave divers Florian and Annka Ungermann are venturing in to this unknown world.

-So the area here, the whole area, is very famous for cave diving.

I would say it's even one of the best spots in Europe to go cliff diving, definitely.

-So, yeah, this is a kind of special area for cave diving.

In Germany, where we are from, um, yeah, it's just not really possible.

Yeah, it's kind of relaxing because nobody can talk to you and can only do some small communication with your hands, and the phone is out and you're offline.

-As they continue their exploration, we continue down the Dordogne.

110 kilometers from where we began, we reach La Roque-Gageac.

Many houses are cut right into a limestone cliff offering shelter from invaders, a practice dating back a thousand years.

Helene Du Tarde family haven't been living on the river quite that long.

They moved in 600 years ago.

Part of her home needs renovation, but one of the many benefits of owning a medieval tower house is that when the door handle breaks, you can get inside with a sturdy plant stem.

-Sometimes we come here because we can feel the history of this very, very old place and we love it.

-History here runs deep.

The building was once part of a larger castle for the local bishop.

Later it housed the local blacksmith.

-To have a very, very old house, you are not in your house.

You keep the house to give it for others.

And it's a very good feeling to know we have a lot of ghosts and they are watching you.

-But the real surprise is not the house, it's the former family farm.

-Welcome to the gardens.

♪♪ Hidden on a small riverside plot, an Asiatic garden with 50 different varieties of bamboo.

-Every day I go here to hear the birds and to feed the squirrels.

It's very, very cool in summer, and some say it's very Zen.

-And hidden within the bamboo, a 400-year-old dovecote.

Pigeons were kept here for eggs, meat, and believe it or not, their poo used for fertilizer.

-Each case was for one pigeon.

Some visitors ask us and say to us, "But that was to put bottles of wine."

No, no, no, no.

[ Chuckles ] No, no.

-No.

Definitely not the place to keep wine.

It's been many a year since people kept pigeons here.

But in a nearby field, we'll find another kind of flock.

A squadron of hot air balloons preparing to carry us along, or rather, above the Dordogne towards our next destination.

Like many birds, these creatures are somewhat ungainly on the ground.

But in the sky, it's a different story.

♪♪ We are continuing our journey on a hidden river of air with balloonists Cedric and Laurent.

-Just flying, you're just lifting in the air and playing with the elements.

It's just, like, it's awesome to me.

-But don't be fooled by his relaxed demeanor.

We are slowly drifting into a battleground.

♪♪ Dawn breaks over a typical autumn day on France's river, Dordogne.

At first light, moist night air condenses into an enchanting mist over the landscape before clearing in the midday sun to reveal a fairy tale world.

Six centuries ago, this area was not a playground for hot air balloons.

It was the center of a bloody struggle -- The Hundred Years' War.

And the Dordogne itself was the front line.

The north side of the river, including La Roque-Gageac belonged to France.

The south bank was controlled by the kings of England from their fortress at Castlenaud.

Today, curator Letitia Bortolussi welcomes all visitors.

But in the 14th century, the French were most unwelcome, though they often came anyway.

-The castle of Castlenaud suffered many attacks during the Hundred Years War.

It changed camp 11 times, exactly.

-It's easy to see why Castlenaud was such a great prize.

Whoever held this commanding position overlooking the Dordogne, controlled the vital gabarre trade route.

More importantly, from the English perspective, there's a clear view of the French foe at the rival castle of Beynac, barely three kilometers away on the opposite bank.

The Lords here clearly believed in keeping friends close and enemies closer.

-So the Dordogne Valley was in fact the valley of five chateaus exactly.

The one of Castlenaud in this side of the Dordogne River, you have Fayrac at the end of the forest, in front of you on the north, the castle of Beynac, and just in front of Castlenaud, another one -- Marqueyssac.

-When the enemy came calling, they announced themselves with 14th century heavy artillery -- trebuchet.

Letitia can operate this 1/3 scale model all by herself.

-Are you ready?

Okay, so, five, four, three, two, one.

-Nice shot.

But these rubber projectiles don't have quite the impact of the original 150 kilo stone balls.

They could literally punch a hole in a castle wall.

-It was the most efficient, the most precise, accurate war machine.

Every projectile will touch exactly the same point on the wall in front of the machine.

In October 1442, the King of France, Charles VII, decided to put an end to the English supremacy here.

-A three week siege, backed by a battery of trebuchets, marked the beginning of the end for England's European empire.

-11 years after this offensive here in Castlenaud, the King of France succeeded to put an end to the Hundred Years' War.

During the famous Battle of Castillon, where the English army suffered its biggest defeat.

-Well, you win some, you lose some.

But though the Dordogne is now forever French, most people have moved past this age-old rivalry.

-[ Speaks native language ] -Rugby fan and boatman Pierre Lavalle may believe that sport is just war minus the shooting, but there's little danger of coming under attack here these days.

Nevertheless, the shallow river is filled with hazards that can ground the boat.

Luckily, Pierre knows what he's doing.

-[ Speaks native language ] -10 miles downstream from La Roque-Gageac the Dordogne winds through France's great culinary heartland, the Perigord.

It's time for something to eat.

To find it, we're visiting a hilltop orchard watered by the Dordogne with this irrigation system.

The prize we're after is not on the trees, it's under them -- black Perigord truffles.

But sniffing one out takes a very particular kind of nose.

-[ Speaks native language ] Meet Pounti, a two-year-old Auvergne Shepherd dog and his handler Adrian.

They work together as truffle hunters.

-[ Speaks native language ] Today they've been brought in by Edouard Aynoud, one of an estimated 20,000 French truffle farmers, to sniff out these valuable fungi, which only grow underground near tree roots.

-You won't have a lot of grass growing because the truffle is releasing a kind of toxin that would not allow the -- the grass to grow properly.

And so this area is the evidence of the presence of the truffle.

And this area is called in French "la brulee," which means the burnt area.

-The best truffles can fetch 1,000 euros per kilogram, but it's an uncertain business.

-I have one tree can give -- It is my champion -- can give in winter... Four kilos, five kilo.

Okay?

Good tree.

Money, money.

But I have this tree.

This tree, no give truffle.

Never give truffle.

Why?

I don't know.

-We are going under the cherry trees over there.

-Though Adrian and Edouard have an inkling which trees might be productive.

actually finding nuggets of black gold is next to impossible.

At least, impossible for humans.

-[ Speaks native language ] -For Pounti, the hard part is resisting the urge to dig the truffle out himself, which might damage it.

-[ Speaks native language ] The real problem about truffle hunting is the human.

The dog's always right.

[ Speaks native language ] So you see, this one is having a little white color.

That's why we always ask the dog to stop because you don't want him to damage the truffle.

Because when you get on the market, the damaged truffle will be less, will cost less.

[ Speaking native language ] -The best.

You want smell?

-Pounti gets rewarded the way any French dogs should -- with cheese.

-[ Speaks native language ] We only give the -- the reward when the dog find the truffle because otherwise, uh, it will scratch everywhere.

You know, just pretending that he found something.

-[ Speaks native language ] -Teamwork, as they say, makes the dream work.

-It's more than a just a pet, it's actually your work mate.

And so I've been very lucky, actually.

Very lucky because he's a good dog.

He's a good dog.

-When we return to the Dordogne, we'll be seeing it from a unique perspective as we break out our brushes and find a dash of artistic inspiration.

-It's called L'Esperance, the River of Hope.

It's always got a little twinkle and a shine to it.

-We're halfway along the shallow waters of France's river, Dordogne.

Almost 150 kilometer from where we first began, we've arrived at the Panoramic Gardens of Limeuil We're meeting English artist Adam Cope to experience one of the river's most enchanting viewpoints... allegedly.

-What I call the valley spirit, breathes -- it breathes humidity.

The cool evening and the warm air makes the mist sit in the valley every single morning.

So you do get these white outs and they they'll start raising around 10 or 11:00.

-Adam should know, he's been living and painting in the Dordogne for more than 25 years.

-So it's not Provence here because you've got all this humidity of the Atlantic, but you have the strong southern sunshine and the green golds of the Dordogne are just the most bestest color ever.

So there you go.

I mixed up a tube of it already.

So I'm just laying a primer down to -- to make my whites precious.

-It turns out Adam doesn't need to see the river in order to paint it.

-This is my usual spot, yeah, I confess I've actually painted this spot quite a few times.

[ Chuckles ] But there's always something interesting in it.

-By noon, Adam's favorite view finally comes into view, revealing both the Dordogne and a tributary, the Vezere.

-It's kind of like where the Dordogne suddenly becomes middle age.

The two rivers, when they bang in together, they get wide.

It's called L'Esperance, the River of Hope, locally.

So it's always got a little twinkle and a shine to it.

Fast moving water over stones.

And for a painter, you know, what more do you need?

What more do you need?

-The problem now is the misty morning scene of Adam's imagination is bumping into the reality of another perfect sunny day.

-Now the sun is very strong.

It's now contoured into the daylight.

So I'm now going to turn the painting around to actually have a look at the colors correctly.

Yeah, I think the mists are quite nice.

Got the bend, got the browns and the Vezere.

Happy with that.

It's nice.

♪♪ -As we move on, the Dordogne is now wider, yet still dangerously shallow in places.

En route to our next stop is a now disused canal built to bypass perilous rapids on the edge of the Dordogne's largest town, Bergerac.

The handsome buildings that crowd the medieval town center, a testament to the riches of the river trade.

Those riches were brought, of course, by gabarre which still ply the river today, carrying tourists.

Philipe Lapawa was once one of those tourists.

Now he serves as a guide.

-I come here for the holidays, and I fall in love of this region.

And my wife, too.

And so we decided to come here.

-With the last of the rapids behind us, the river is now navigable both ways, so these gabarres have sails allowing them to move upstream as well as down.

-On the 17th century, you have 20,000 sailors working on this boat and in all the Dordogne River.

-Bergerac was the bustling hub of this vital trade network, and there was one cargo that dominated everything.

-So the main stuff we put on this boat was wine.

They put more or less 8,000 to 10,000 kilos in this boat, but this boat is going down inside the river, only 40 centimeters.

And this is the most important because in a lot of parts in the river, we have only 60 centimeters deep in the middle.

-As we leave Bergerac, the Dordogne carries us towards some of France's most storied wine country, surrounding the village of Saint-Emilion.

Its handsome limestone streets are home to more than a few wine merchants.

So let's have a drink.

-We'll be drunk by noon.

[ Laughs ] -With just over 1,000 permanent residents, Saint-Emilion may be small, but it's mighty.

Built on the site of a former limestone quarry, the town dramatically spills down a man-made cliff, while a huge 12th century bell tower shoots above it like a medieval rocket ship.

Over 5,000 hectares of vineyards radiate out from the center, producing some of the finest vintages on earth.

One of the smaller wineries here is Chateau Ambe Tour Pourret.

-We often say that in Saint-Emilion you only find huge wineries when you're not really welcome.

What I like about this winery is quite small.

It's really a family winery.

-Winemaker Celine Lenoye has two hectares of organic vines growing a classic combination of Merlot and Cabernet Sauvignon.

But what gives her wine its character is a distinct combination of soil and microclimate created by the Dordogne, which passes close by what the French call "terroir."

-We'll always find a vineyard close to a river.

It brings a balance in the weather.

Not too much sun, not too much rain.

So it's something also really important.

-Elsewhere in Saint-Emilion, the annual harvest has begun.

Each year, workers pick around 43 1/2 million kilos of grapes, making 13 million bottles of wine.

But Celine is waiting for just the right moment.

-What we need to do now is to taste really often the grapes, just to know if they are ripe enough to be harvested.

You need to see if the skin is very thin or not.

So if it's thin, it means it's riper, so it's better.

And also you will look at the seed inside.

If it tastes nuts it means it's almost ready to harvest.

-After harvest, the grapes are fermented in either stainless steel or concrete tanks, each of which imparts a subtly different flavor, and then to a climate controlled cellar for aging in the time honored way -- with French oak barrels.

But there's only one way to know when the wine is ready for bottling -- by tasting.

-You have a lot of strawberry notes, because also it's quite young and it's already really well balanced.

I think it can stay a little bit longer in the barrels, so we wait a couple more months before getting the wine out.

-Ah, the life of a winemaker.

Spending all day, every day tasting wine.

But please note that's tasting, not drinking.

-We always spit because we do a lot of tasting.

So if we were only drinking every glasses, we will be drunk by noon.

[ Laughs ] -From Chateau Ambe Tour Pourret it's a short drive back to the last major town on the river, Libourne.

As another tributary, the River Eel merges with the Dordogne, it's now navigable by far larger vessels.

So our journey to river's end will be on board the 110 meter long luxury river cruiser, the S.S. Bon Voyage.

-So here's the cheese we bought from the market.

-Head chef Franck Chavaud likes to pick up local produce whenever the ship is in port.

-We got three kinds of goat cheese.

This is the oyster we bought from the market this morning.

We will open them for lunch.

I love the region because I'm born here.

You know, when I was a kid, I would go to the ocean with my parents.

We have family close to here as well.

So we went a lot of times.

Very nice.

I like a region.

Nice wine, nice food.

-On deck, the crew are busy readying the ship for departure.

As the guests tuck into Franck's gourmet buffet in the restaurant... we shove off, setting sail for the river's end.

♪♪ ♪♪ Today, we are under the watchful eye of Captain Romain Cordier, who at just 34, is one of the youngest river pilots in France.

-I'm born in Bergerac, another city on the Dordogne, so I have a very special feeling with the river.

-80 guests have signed on for an eight day cruise, staying in one of the 62 suites or staterooms.

Food and drink is in five different bars and restaurants.

And if they fancy, there's the onboard pool.

With the help of 50 staff and crew, Romain looks after them all, as well as the 10 million pound ship itself.

But don't be fooled by his relaxed demeanor.

This is not as easy as it looks.

-This streams the current, the tide.

The tide -- The weather change very fast, and we have to adjust our sailing all the time.

-And although we are still 110 kilometer from the sea, the river's wide open path allows the ocean tides to flood in and out.

Being in the wrong place at the wrong time could lead to disaster.

-If you make a mistake of one hour, we can stay stuck, we can not move.

Worse, like everywhere else on the Dordogne, the river here is remarkably shallow and full of hidden hazards, including shipwrecks left by fleeing Germans at the end of the Second World War.

Even when the timing is right, there can be just inches to spare between hull and riverbed.

-On the Dordogne River, I already sailed with 30 centimeters under the hull.

It's, uh...

It's not funny, really.

It's not a good time when you do that.

With the tide, you can make this kind of problem.

But thanks to a mix of skill and computer-assisted steering, Romain can slip this enormous ship through the tightest of gaps while his guests only notice the scenery.

-It's been beautiful.

-Yeah.

And the drinks are really good, too.

[ Chuckles ] -My favorite part is in the summer, especially in the morning.

Early in the morning, because, uh... the sunrise are beautiful.

Just beautiful.

It's, uh, I don't know.

I don't see any sunrise like that on the other river.

It's very something special.

-We are close to the end of the river, but our magical journey will continue as we head out to sea, and a hidden marvel of France's royal grandeur.

-"When the world will end, this lighthouse will proudly stand."

-We're on a journey from France's lush volcanic highlands to the wild Atlantic along the river Dordogne.

We've been traveling by traditional gabarre from the Dordogne largest town, Bergerac, past the manicured wine chateaus of Saint-Emilion to the old wine trading river port of Libourne.

We'll be finishing our voyage out at sea at the unique Cordouan Lighthouse.

42 kilometers from Libourne we're on board the luxury river cruiser, the S.S. Bon Voyage .

We've reached a headland which marks the point where the Dordogne merges with another of France's great rivers, the Garonne.

-We just leave Dordogne now, Dordogne is back of us, and we are going to reach Bordeaux now for the end of our cruise.

-As the Bon Voyage leaves the Dordogne, we leave the Bon Voyage to cross Western Europe's largest estuary, the Gironde, soon reaching the coast at Le Verdon-sur-Mer.

But this is not the end of our adventure, we're boarding another boat to sail seven kilometers into the Atlantic to France's oldest lighthouse, Cordouan The Dordogne's curse of shallow water seems to have followed us all the way out here.

The lighthouse is built on a partially submerged sandbank, and if the ship gets too close, it will run aground.

Which is why we've brought along a friend -- this all-terrain landing craft.

Waiting to greet us is one of the two resident staff members, Thomas Dallison.

-Bonjour, Monsieur.

Bonjour.

[ Speaks native language ] -This is one of the last manned lighthouses in Europe, but the light itself is entirely automatic.

So Thomas doesn't like to be called a lighthouse keeper.

-We are guardians, we are here to look after the building.

We are here to take care of it.

Every year we repaint everything that needs to be painted.

Every year we scrap everything that's rusted.

I mean, we just take care of the place.

-And what a place it is.

Completed in 1611 under King Henry IV, Cordouan is a Renaissance masterpiece, complete with an extravagant chapel.

Here the architect Louis Dufour left a poem for his master.

-And he speaks in a very informal way to the king.

He says, "You got by the building of this lighthouse so much honor that when the world will end, this lighthouse will proudly stand."

-In the end, no king ever set foot on this so-called lighthouse of kings.

But one distinguished person who did visit was scientist and inventor Augustin Fresnel.

In 1823, he installed a new type of lens here, with an experimental design that makes light appear brighter from a greater distance than anything seen before.

The Fresnel lens was so effective that it was installed in almost every lighthouse in the world.

♪♪ The sea is amazing.

The views, everything.

I mean, it's changing every day.

The building itself is amazing.

I love this place.

-As the sun sets on the broad ocean more than 500 kilometers from where the Dordogne begins, our adventure is at an end.

It's been an incredible journey down a shallow highway shaped by nature, by conflict... and by the rich resources of this region.

Though its once busy waters are now quiet, for those who live, work, and play here, it's still very much loved.

♪♪ ♪♪ ♪♪