Legend of Atlantis (Full Episode) | Drain the Oceans

♪ ♪ NARRATOR: Lost civilizations. Mysterious sunken cities. And legendary Atlantis itself.

Vanished beneath the waves. PATRICK: There is a huge amount of unrecorded human history beneath the ocean's surface that we don't know very much about at all. NARRATOR: Imagine if we could empty the oceans, letting the water drain away to reveal the secrets of the sea floor.

Now we can, using the latest underwater technology. Piercing the deep oceans and turning accurate data into 3D images. Is this a huge underwater temple carved by a mysterious lost civilization?

NARRATOR: Why are these perfectly circular stones lying at the bottom of a bay in the Aegean Sea? SIMON: There are shapes on the seabed that just don't make sense. NARRATOR: Are these just rocks, or the remains of an ancient city?

JON (over radio): Parts of this are just beginning to be revealed for the first time. Wow. NARRATOR: And is the real site of Atlantis finally about to be revealed?

-People want to believe in places like Atlantis. They want to believe in other worlds. (waves crashing) NARRATOR: Stories of sunken cities have fascinated for millennia.

The most tantalizing of all: Atlantis. First described by ancient philosopher, Plato, a dazzling civilization destroyed by the gods as punishment for human pride. -People connect to that story, and it's because of this idea of an ancient civilization, a utopia, that we've evolved from.

NARRATOR: 2,000 years later, the idea of Atlantis continues to fascinate A-list archaeologists. And the producers of B-list movies. MAN (over TV): Atlantis is the story of those who, like today, would use the marvels of science to conquer and enslave.

Atlantis, a world that worships strange gods of science, of science, a science gone berserk. -Plato would have loved this okay? He would have had a great time.

He would have said, 'at last, you know, people are listening to me. People are taking my story seriously. ' And he would have enjoyed this immensely.

NARRATOR: Using science, not science fiction, draining the oceans exposes new evidence about Atlantis. And other stories of great sunken cities, around the world. As the waters recede from around the remote Japanese island of Yonaguni, a mysterious formation begins to appear.

Could it be the creation of an advanced, ancient people? Yonaguni lies in the East China Sea. The waters here are perilous.

Schools of hammerhead sharks patrol, amid powerful currents. Typhoons frequently batter the island. For divers, it's the ultimate challenge.

Kihachiro Aratake is one of the pioneers of diving here. KIHACHIRO: The water was crystal clear. I felt as though I was looking down from the seabed from the sky.

NARRATOR: Searching for a new dive site, he makes a startling discovery. -I saw a steps-like formation, like terraced fields. I thought for a moment it was similar to the Machu Picchu ruins.

So, I named the spot the submarine ruins. NARRATOR: It's an extraordinary spectacle. The size of five football fields.

Smooth-sided walls rise up to the summit, the height of an eight-story building. Flights of stone steps climb up from the base. And on every side, the shapes and forms are strikingly regular.

-It can't be formed naturally, without human involvement. It couldn't be like that. NARRATOR: So, what could it be?

It's impossible to investigate the structure fully by diving. The only way is to conduct a survey using the latest scanning technology. HIRONOBU: Although the shallow waters around Yonaguni Island are close to human habitation, we don't know much about them.

It's an unknown frontier. NARRATOR: Using sonar scans, Hironobu Kan records a complete digital map of the sea floor. Using this data, it's possible, for the very first time, to drain away the waters and reveal what lies beneath in exact detail.

The summit of the mysterious structure begins to appear. (waves crashing) Water pours off its smooth terraced layers, exposing them once again to the sky. And with the monument left high and dry, its true scale becomes clear.

Vast, imposing and spectacular. The incredible discovery attracts worldwide attention. Divers, journalists and TV crews flock to Yonaguni, all asking: what could this mysterious structure be?

And scientists come here too. Among them is Professor Masaaki Kimura, one of Japan's top marine geologists. KIMURA: When I dived underwater to explore it I felt right away that it must be a man-made structure.

NARRATOR: He finds several features that he believes indicate human activity. -Here, you'll see something that looks like the front gate of a castle. It's like a tunnel, and you go through it.

NARRATOR: On the far side of the tunnel, a road loops around to a flight of steps. Watched over by two mysterious stone objects. -There are mound-like bulges here and here, and if you look at them, you'll find turtles with their necks extended, on both sides.

NARRATOR: According to ancient Japanese folklore, the dragon god, Ryujin, lives in an underwater palace, watched over by turtles. To Professor Kimura, this indicates that the monument is so important it needs guarding. And that's not all.

-If you go up this path you get to this place. This portion is triangular. That's why it's called the triangle pool.

Since this is fairly big and shallow as well, you can relax in it. Also, the sea surface is very close to it and it's warm due to the sunlight. You feel chilly after you come out of the deeper area down there, and you can warm up here.

NARRATOR: But the monument's most striking feature is its wide, flat terraces, Large enough to support thousands of people. Professor Kimura believes the gateway, stairs, turtles and terraces all point towards one purpose. -Judging from its shape, I think they used it as a castle.

NARRATOR: But to prove his theory, Professor Kimura needs more: the artifacts of those who once lived here. He scours the structure looking for clues, and discovers what look like primitive tools. Then, hidden behind one of the great walls, the most remarkable find of all.

-Look at this, a symbol is inscribed here and here's a hole. Probably, they hung this article like this. And here's something looking like a letter.

Maybe it could be a kind of a talisman to protect people from evil. NARRATOR: For Professor Kimura, the case is closed. The artifacts and the monument's regular shapes prove that humans lived here, 8,000 years ago.

After that, rising sea levels claim the territory of this lost race of master builders. But is that the real story of Yonaguni? NARRATOR: Professor Kimura believes that this extraordinary structure off the coast of Japan is a gigantic castle, built long before the pyramids of Egypt by a mysterious lost civilization.

But is it? With the water drained away, it's possible to scrutinize the monument in forensic detail. The edges appear regular and straight, as if made from blocks carved by human hand.

But closer examination reveals something else. The surfaces are smooth and unbroken. The monument is not assembled from handmade blocks, but is in fact one solid mass of rock.

HIRONOBU: The pyramid area and the headland behind it are connected with each other. The surface of the terrain has a lot of grooves, so you may think they are separate, but since they consist of the identical stone, they are originally connected. NARRATOR: The basic form of the monument is clearly natural.

But what about the gateway, steps, turtles and pool? Could it be that an ancient people carved into this huge rock, transforming it into a great castle or temple? Studying the headland on shore provides the answer.

The shapes here are strikingly similar to those found on the monument, and that's because they were formed in exactly the same way. Both are made of sandstone which, when subjected to stress, such as during an earthquake, can fracture along vertical faults, forming angular shapes and what look like steps. PATRICK: Put something like that underwater, have the water wash over the top of it and clear away all the debris, and you've got very, very fine step-like structures.

But they're no more human made than any other structure down there. NARRATOR: The lack of tool marks is further confirmation. The forces which shaped this remarkable place are geological.

But what of the artifacts? Perhaps the monument, if not built by ancient people, was inhabited by them. Walking these steps.

Crowding these natural terraces. But so far, no other objects have been found, suggesting that the talisman and tools were dropped from a boat passing overhead, landing on the monument simply by chance. -The clear thing for Yonaguni for me is there's no pottery, there's no evidence of actual human occupation.

There's not a single wall from the site. There's nothing on it, that indicates human activity. NARRATOR: The Yonaguni Monument is an extraordinary natural formation, created by epic geological forces.

But its shapes appear so regular that many still believe it holds a secret, ancient purpose. JIM: You can take that leap if you have an imagination and say yes, this could be an ancient city beneath the sea but in the case of Yonaguni I'm in those ranks that feel that it's not. It's geology.

-We want to believe that science doesn't have all the answers. We want to believe innately that there is something out there that we can connect with spiritually and that hasn't really been polluted by being the subject of scientific discovery. NARRATOR: And still amongst the believers is Professor Kimura.

He remains convinced that the monument was inhabited by his ancestors and continues to search for evidence to prove the doubters wrong. Beneath the oceans of the world lie many more tantalizing traces of possible lost civilizations. As the water continues to drain away, in the Eastern Mediterranean, astonishing structures emerge in a quiet island harbor.

Is this jumble of shaped stones the architectural debris of a once great city? Alikanas Bay, a tourist hotspot on the island of Zakynthos, Greece. Diver, Pavlos Voutos, sets out to take some underwater photos.

NARRATOR: Pavlos swims farther out into the bay in search of clearer water. Then, out of the gloom, he sees something that will change his life. NARRATOR: The debris stretches out for hundreds of yards in all directions.

The area is so large that Pavlos is convinced he's found the remains of an entire town. NARRATOR: The discovery sends a bolt of electricity through the world of archaeology. Professor Michael Stamatakis, immediately travels to Zakynthos to investigate.

NARRATOR: Stamatakis recalls seeing similar shapes on land, at the site of an ancient settlement built over 2,000 years ago. NARRATOR: If the same shapes lie on the sea bed, they could indicate an ancient settlement just offshore concealed under the bay and forgotten about for centuries. Comparing the images is not enough.

The only way to reveal a complete picture of the structures is a detailed underwater survey. Simon Brown is an expert in 3D modelling. But the task facing him is immense.

SIMON: Right now we're not quite sure how big the area is. I've estimated it's about 16 acres, which will be more than double the largest subject I've ever covered to date. It's a weird place.

There is definitely features here that I have never seen anywhere else before. They look out of place. But then I started to see more regular shapes that looked that cut stone.

So my mind then starts to think, is it. . .

is it manmade? NARRATOR: Can draining the waters of the Mediterranean provide the answer? NARRATOR: Simon Brown is mapping mysterious underwater structures discovered in a Greek bay.

Could they be the remains of an ancient town? He takes nearly 4,000 high resolution photographs of the sea floor tracking each with pinpoint accuracy through GPS. Using these images, it's now possible to do something which has never been done before: drain the waters of Alikanas Bay and reveal, for the first time ever, a 3D plan of the entire sea floor.

As the Mediterranean begins to recede, a world is exposed that's been invisible for thousands of years. First, the rocky shoreline is left high and dry. Then, from the dark depths, regular shapes begin to appear, hidden amongst the rocks.

Could they be the bases of stone columns which together once formed a grand colonnade? The use of colonnades is a turning point in ancient Greek architecture. Builders can now switch from wood to stone, a far stronger material, to create ever larger temples to the gods.

A colonnade in Alikanas Bay would prove that an important, ancient settlement once stood here. But some experts remain skeptical. PATRICK: There are structures all over the world that mimic something that humans may have created.

Doesn't mean that humans created them. NARRATOR: With the water drained away, it's now possible to search the sea bed for evidence of human occupation. Fragments of the pots people cooked with.

Charcoal from their fires. Tools for farming, and weapons for defending their homes. Any objects made of metal, clay or stone should have survived.

But there's nothing. Which means these extraordinary remains, whatever they are, are not the relics of a lost town. So, what are they?

NARRATOR: Further analysis reveals the formations are what geologists call 'concretions'. Solid blocks of sedimentary rock formed by powerful volcanic activity. Underwater vents release methane from deep within the Earth.

Combining with microbes and sediment, the methane causes regular circular shapes to form. Far from being a relic of ancient Greece, the structures here pre-date human activities by five million years! Despite all the evidence against his theory, Pavlos Voutos remains convinced that the fantastical landscape he discovered was shaped by his ancestors.

NARRATOR: Classical civilizations dominate the Mediterranean for over a thousand years. Today, all around its coast, people tell stories of sunken cities. As the waters around Greece drain away further, an extraordinary underwater vista is exposed.

Could these patterns on the sea floor be the remnants of an ancient city? The village of Elafonisos sits on a small island just off the Greek coast. At first glance, an ordinary fishing port.

But in 1967, less than 100 yards out to sea, something attracts the attention of a visiting maritime archaeologist. Snorkeling in 13 feet of water, Nicholas Fleming catches a glimpse of regular shapes on the sea floor. Then, exploring deeper, he sees what he thinks is evidence of human activity.

FLEMING: I looked at these rows of stones, and I just had no idea what it was, but I realized immediately that it was manmade, that we were looking at a large part of a town, and I mean I just went crazy. NARRATOR: Fleming is convinced he has found something special. But could these simply be natural formations, mimicking human structures, like the concretions of nearby Alikanas Bay?

The following year, Fleming returns with a team of surveyors to discover the truth. Using tape measures, they document what they find. And the results are astonishing.

The site is strewn with signs of human activity. Pots, storage vessels and tools lie across a huge area of the sea bed. There can be no doubt: Fleming has discovered the remains of an ancient town.

It's named Pavlopetri after a nearby island. But who built it, and when? These questions inspire a generation of archaeologists.

JON: Well I've always been interested in submerged settlement, submerged towns, and I'd read about Pavlopetri as a boy. And this idea of an intact, prehistoric town underwater just seemed you know incredibly romantic, incredibly exciting. NARRATOR: Henderson can now fulfill a childhood dream and explore this haunted underwater world for himself.

-Here we have a quern stone. -You can see it's got a very concave, concave surface there. That's for grinding grain or whatever it was that you were turning into you know flour.

That's quite a clear artifact. Very nice. There is a huge amphora.

One, amphora, two amphora, three, four, five. This gives you an example of what's coming out of the sand, what's eroding out of the sand. Look, there's the base of an amphora, there's the amphora shape there, it's on its side.

There's another one next to it and another one there. NARRATOR: And further into the bay, more evidence of human life, and death. -So, here's a cist grave.

Edge set slabs. A very small one. Possibly for a baby.

There are about 40 of these on the site. NARRATOR: Diving gives intriguing glimpses of objects lying upon the sea bed. But it's impossible to gain a complete picture.

To do this, it must be mapped using the latest in underwater scanning technology. (waves crashing) Using this data, it's now possible to drain away the waters above Pavlopetri and bring sunlight back to a forgotten world and a true Sunken City. With the entire bay drained away, everything becomes clear.

The lines are the foundations of buildings, laid out in clear streets. At the heart of the town is a large open area, perhaps an ancient market place. And nearby, the remnants of a huge structure, perhaps an important civic building.

The remains cover 20 acres and the town could have housed 4,000 people. A thriving, ancient settlement once existed here. The next challenge is to discover who built it.

And when. -We know how old the occupation of the site is, because we've got pottery. And pottery particularly in this part of the world is very well dated.

What was really exciting is we actually found evicdence of pottery from the end of the Stone Age. So, we've actually got occupation here from about 5,500 years ago. And then we've got every single bit of pottery you would expect up until about 1100 BC.

There's no gaps in that. So, the place seems to have been continuously occupied throughout the Bronze Age. NARRATOR: Pavlopetri was occupied for 2,400 years during a revolutionary period of human development.

At its peak in the bronze age, around 1700BC, it looked like this: a perfect example of the time when Europeans start to live in stone-built towns with regular laid out streets. But one question remains. Why did the builders of this town choose this particular location, in a remote part of ancient Greece?

Exploring the drained landscape around the ancient city reveals an all-important clue. At its edge, a huge sand bank stretches out into the ocean. During the Bronze Age, people don't build ports out of stone.

They bring ships up to the shore and then beach them. And Pavlopetri's location means it can exploit the trade routes that boom during the Bronze Age right across the Mediterranean. Evidence of early commercial activity is everywhere.

-The interesting thing is we've clearly got a lot of material coming in. We found thousands and thousands of shards of very large storage vessels, which have been used for storing olive oil, wine, that kind of thing and generally anything. They were like the containers of the day.

NARRATOR: And that's not all. Pavlopetri is also a hub for manufactory. -We've got a lot of evidence for loom weights, thousands of loom weights, way more than you would need for domestic production so it seems that maybe textiles were something that were being produced on the site and perhaps exported.

NARRATOR: Pavlopetri is an extraordinary, bustling, vibrant port city. And an important center of trade. So how did such an advanced metropolis meet its end?

NARRATOR: An ancient, submerged city off the coast of Greece. How it came to lie on the sea floor is a mystery. JON: One of the interesting things about Pavlopetri and its submergence is that there are no historical references to it at all.

It sunk under the waves and then it was out of sight, out of mind. And there's certainly no classical sources that refer to its sinking. And there's nothing until it's discovery really in the 20th century.

NARRATOR: Scanning the drained bay could reveal what happened to Pavlopetri. At the edge of the town, it's possible to make out three mysterious lines. These are strips of beach rock, formed by the action of sunlight on salt water.

They form only near the shoreline. It can mean only one thing: earthquakes caused this land to subside into the sea. -So, there was a big earthquake, perhaps part of the remains went under the water, part of them are still surviving, then there was another earthquake it was pushed under then there was a third, and it was gone.

NARRATOR: Pavlopetri is one of the most important Bronze age sites in the world, and the oldest submerged town ever discovered. But it's not alone. -A lot of the major finds in the next couple of decades are going to come from the sea.

I think we have the potential to rewrite what we know about human history. NARRATOR: Pavlopetri is an extraordinary find, but it is not the legendary Atlantis. Various locations for Plato's dazzling city have been proposed, around the world.

But most academic investigations point to one place: the Mediterranean. As its waters continue to drain away, at its western end, new and tantalizing evidence is revealed. Could archaeologists finally have found the site of Plato's famous lost city?

Marc Gutscher is a geophysicist, long fascinated by Plato's story. MARC: I do think that becoming interested in Atlantis can be almost, like a bug or an infection or like gambling. I think one can become obsessed.

NARRATOR: Plato wrote about Atlantis in 360BC, describing an advanced metropolis 9,000 years before his own time, lost beneath the waves in a cataclysmic event. Marc Gutscher has analyzed Plato's texts, searching for clues to its location. -'This power came forth out of the Atlantic Ocean from an island situated in front of the straits which are by you called the Pillars of Heracles.

' NARRATOR: The Pillars of Heracles is the name given by Plato to the maritime boundary of the ancient Greek world. Many locations have been suggested. But Marc believes he has the answer: The Straits of Gibraltar.

-So here at Cape Spartel we're at the northern edge of the Moroccan Atlantic coast and just at the entrance to the Straits of Gibraltar. About 10 to 15 kilometers off to the north west there's a submerged bank. Some people have suggested that it might have been inhabited and it might have formed the origin of the Atlantis legend.

NARRATOR: Today, this area sits under the second busiest shipping route in the world, a difficult place for sub-sea investigation. During a project to study rising sea levels here, Marc gets his chance. Using a remotely operated vehicle or ROV, he sets out to map the sea floor.

(waves crashing) It's challenging work. -It was very difficult, both the towing of the camera was difficult, keeping the ship in place was difficult, and especially trying to keep the ROV in place was really, really difficult. NARRATOR: Finally, Marc gets the sonar scanning data that he needs.

Now, combining this information with the latest computer graphics, it's possible to drain away the sea water from between the ancient pillars of Heracles, and attempt to solve one of the greatest archaeological mysteries of all time. . .

Soon, rocks begin to emerge, and the unmistakable outline of an island gradually appears. Is this the site of Atlantis, exposed for the first time in 11,000 years? Once again, important clues lie in Plato's own writing.

-Plato says that the city, and all of its war-like men, were destroyed in one day and night of terrible misfortune, caused by strong earthquakes and floods. NARRATOR: The island revealed by draining the ocean, sits on a subduction zone, a boundary between the huge tectonic plates that make up the Earth's surface. The exact point where the biggest earthquakes strike.

A series of powerful earthquakes and tsunamis could have obliterated Atlantis and sent the island on which it rests down into the ocean depths. -You could imagine that during great earthquakes there might have been some subsidence, so if we were to take into account maybe 20 or 30 meters of subsidence due to those earthquakes, there might have been a somewhat larger island there. NARRATOR: The geology supports Plato's account of the destruction of Atlantis.

But one other vital piece of evidence is still needed. NARRATOR: Drining the ocean has revealed a mysterious island exactly where Plato said Atlantis would be. But one other piece of evidence must be present for it actually to be Atlantis: The remains of substantial man-made structures.

Using the drained landscape, it's possible to study the island's surface in extraordinary three-dimensional detail. Searching carefully for the remains of walls, temples, bridges, and anything constructed by human hands. But there are none.

Nowhere on this mysterious island are there any lines or geometric shapes which would indicate the presence of a great, ancient city. MARC: Atlantis did not exist in the tiny island of Spartel. If it did exist traces of it have not been found.

NARRATOR: However, the story of this submerged island is not over yet. There may be no trace of a city built out of stone. But evidence found on land nearby suggests that during the Stone Age, when sea levels were much lower, people did live here and in many other places just like it.

And during this period, our human ancestors make some of the most important breakthroughs of all time. They learn how to farm, keep domesticated animals, use sophisticated tools, build wooden houses and begin to trade. Then, the last Ice Age comes to an end.

Over the course of 15,000 years, sea levels rise by 400 feet. And the territory of these early people vanishes. Their tools, homes and weapons are washed away.

That elemental human story may help explain the timeless appeal of the Atlantis legend. PATRICK: There are many, many stories out there in the world that recall times when land that was once inhabited was submerged. Did that information inform Plato's fiction about Atlantis?

JON: I think there's no doubt, that almost every culture in the world has a flood myth, a deluge story, because we developed, as a species, within this period of rising sea level. So, that for me, is so fundamental to understanding ourselves as a species, that we should be looking into this. NARRATOR: Plato's story of Atlantis is about human folly and the destructive power of nature.

Today, the rising level of the oceans threatens all coastal communities. Great port cities like Bangkok, Ho Chi Minh City and Dhaka are all at risk. And in North America there's one of particular concern.

New Orleans. Sitting on the banks of the great Mississippi River, the city's average height is six feet below sea level. This makes it highly vulnerable to flooding.

In 2005, disaster strikes. Hurricane Katrina causes a massive storm surge and the levees, designed to protect the city, are breached. The resulting floods are catastrophic.

Nearly 2,000 people die and many more are left homeless. And the situation in New Orleans is getting worse, because the city itself is sinking. Due in part to the removal of groundwater, some districts of New Orleans are subsiding by two inches a year.

JIM: Given ongoing sea level rise, which is a scientific fact, the time will come when some of our settlements in our time are under water. Cities like New Orleans, they all have suffered incursions of water. And the time will come when we will no longer be able to battle that incursion.

NARRATOR: By the turn of the next century, New Orleans could be uninhabitable. A mysterious underwater city, studied by maritime archaeologists. A modern-day Atlantis.

Captioned by Cotter Captioning Services.