Eastern Mediterranean

The legend of Atlantis, the country that disappeared under the sea, may be more than just a myth. Research on the Greek island of Crete suggests Europe's earliest civilisation was destroyed by a giant tidal wave.

Tidal wave

Until about 3,500 years ago, a spectacular ancient civilisation was flourishing in the Eastern Mediterranean.

The ancient Minoans were building palaces, paved streets and sewers, while most Europeans were still living in primitive huts.

But in around 1500 BC [circa 1470 BC in the History Files] the people who spawned the myths of the Minotaur and the Labyrinth abruptly disappeared. Now the mystery of their cataclysmic end may finally have been solved.

A group of scientists have uncovered new evidence that the island of Crete was hit by a massive tidal wave at the same time that Minoan culture disappeared.

"The geo-archaeological deposits contain a number of distinct tidal wave signatures," says Dutch-born geologist Professor Hendrik Bruins of the Ben-Gurion University of the Negev in Israel.

"Minoan building material, pottery and cups along with food residue such as isolated animal bones were mixed up with rounded beach pebbles and sea shells and microscopic marine fauna.

"The latter can only have been scooped up from the sea-bed by one mechanism - a powerful tidal wave, dumping all these materials together in a destructive swoop," says Professor Bruins.

The deposits are up to seven metres above sea level, well above the normal reach of storm waves.

"An event of ferocious force hit the coast of Crete and this wasn't just a Mediterranean storm," says Professor Bruins.

Big wave

The Minoans were sailors and traders. Most of their towns were along the coast, making them especially vulnerable to the effects of a tidal wave.

One of their largest settlements was at Palaikastro on the eastern edge of the island, one of the sites where Canadian archaeologist Sandy MacGillivray has been excavating for 25 years.

Here, he has found other tell-tale signs such as buildings where the walls facing the sea are missing but side walls which could have survived a giant wave are left intact.

"All of a sudden a lot of the deposits began making sense to us," says MacGillivary.

"Even though the town of Palaikastro is a port it stretched hundreds of metres into the hinterland and is, in places, at least fifteen metres above sea level. This was a big wave."

But if this evidence is so clear why has it not been discovered before now?

Tsunami expert Costas Synolakis, from the University of Southern California, says that the study of ancient tidal waves is in its infancy and people have not, until now, really known what to look for.

Many scientists are still of the view that these waves only blasted material away and did not leave much behind in the way of deposits.

But observation of the Asian tsunami of 2004 changed all that.

"If you remember the video footage," says Costas, "some of it showed tonnes of debris being carried along by the wave and much of it was deposited inland."

Volcanic eruption

Costas Synolakis has come to the conclusion that the wave would have been as powerful as the one that devastated the coastlines of Thailand and Sri Lanka on Boxing Day in 2004, leading to the loss of over 250,000 lives.

After decades studying the Minoans, MacGillivray is struck by the scale of the destruction.

"The Minoans are so confident in their navy that they're living in unprotected cities all along the coastline. Now, you go to Bande Aceh [in Indonesia] and you find that the mortality rate is 80%. If we're looking at a similar mortality rate, that's the end of the Minoans."

But what caused the tidal wave? The scientists have obtained radiocarbon dates for the deposits that show the tidal wave could have hit the coast at exactly the same time as an eruption of the Santorini volcano, 70 km north of Crete, in the middle of the second millennium BC.

Recent scientific work has established that the Santorini eruption was up to ten times more powerful than the eruption of Krakatoa in 1883. It caused massive climatic disruption and the blast was heard over 3000 miles away.

Costas Synolakis thinks that the collapse of Santorini's giant volcanic cone into the sea during the eruption was the mechanism that generated a wave large enough to destroy the Minoan coastal towns.

It is not clear if the tidal wave could have reached inland to the Minoan capital at Knossos, but the fallout from the volcano would have carried other consequences - massive ash falls and crop failure. With their ports, trading fleet and navy destroyed, the Minoans would never have fully recovered.

The myth of Atlantis, the city state that was lost beneath the sea, was first mentioned by Plato over 2000 years ago.

It has had a hold on the popular imagination for centuries.

Perhaps we now have an explanation of its origin - a folk memory of a real ancient civilisation swallowed by the sea.

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