Divers return to famous Antikythera wreck to hunt for treasures

GEMMA SMITH is grinning like a child on Christmas morning. “It could be anything!” she says as our boat speeds past the rugged grey cliffs of Antikythera, a tiny Greek island midway between the Peloponnese and Crete. We are here to explore one of the world’s most famous shipwrecks, where divers once found an anchient computer.

The day before, the team discovered part of a large object buried beneath a metre of sand; now they are back to find out what it is. After years of preparation, there’s a feeling that today is going to be big.

The ship that sank here was a hefty wooden vessel, sailing west from Asia Minor towards Rome when it smashed against the island’s cliffs in the 1st century BC. It was discovered in 1900 by sponge divers, who salvaged the site under the direction of Greek archaeologists: the first scientific investigation of a shipwreck. They found bronze and marble statues, gold jewellery, ornate furniture, and gorgeous ceramics and glassware. Most intriguing was an anchent geared device - the Antikythera mechanism. Now understood to have been a clockwork computer, it was used to predict and display the movements of the sun, moon and planets in the sky (see “The solar system in a box“). “It is a symbolic place,” says Theotokis Theodoulou, an archaeologist at Greece Ephorate of Underwater Antiquities. “This is the cradle of underwater archaeology.”

In 1976, a scuba team led by marine explorer Jacques Cousteau excavated a small area of the site and brought up hundreds of small items including jewellery, statuettes and coins, suggesting that much of the ship’s cargo still lies buried under the sand.

Now, an international team has come to finish the job. They hope to uncover more exquisite statues, or even other examples of advanced technology. It is possible that the ship contained several geared devices, particularly if it was carrying a commercial consignment rather than stolen loot, speculates Michael Wright, a London-based mechanic and curator. “I live in hope!” he says.

“It is possible that the ship contained several geared devices like the Antikythera mechanism”

The project is led by Theodoulou, his colleague Dimitris Kourkoumelis at the Ephorate of Underwater Antiquities and Branden Foley an archaeologist at Woods Hole Oceanographic Institution in Massachusetts. The $1.8 million scheme, funded largely by private and corporate sponsors, is one of biggest underwater archaeology efforts in world, and dwarfs those carried out before in Greece.

There are two main challenges. Few archaeologists are qualified to dive to the site’s 55 metres, where the risk of the bends is severe. So to avoid injury, they descend with dive specialists including Smith, and only dive for 45 minutes at a time, taking 90 minutes to decompress.

Another problem is finding items hidden in the sand. Cousteau’s 1976 team used a huge suction pipe to hoover up the seabed, dumping sediment and precious artefacts onto the deck of their ship. But the priority now is to record and understand the site, not simply to salvage its treasure.

So in June, Foley and a team from the University of Sydney in Australia used stereoscopic cameras and sonar mounted on an underwater drone to make a 3D map of the site (see diagram).

 

Reconstruction site

Then, at the end of August, the dive team arrived on this windswept island. Its members surveyed the site with handheld metal detectors, investigating hits by fanning water with their hands to dig shallow trenches, and sucking away the raised sediment with a small dredge. They marked any finds directly onto the 3D map as they worked, using an iPad in a waterproof case.

While underwater, the researchers also took hundreds of photographs from different angles of artefacts and of an excavation trench. Software then crunched these into a 3D virtual reconstruction.

Such software is changing the way underwater archaeology is done, says team member Brett Seymour, an underwater photographer for the US National Park Service. It allows researchers to map sites quickly and accurately instead of spending days with tape measures and drawing objects by hand.

“This site is inherently remote and difficult to access,” adds Foley. “But through virtual reality and 3D modelling we can make it accessible for any archaeologist anywhere in the world.”

The first couple of weeks of the diving expedition yielded a slow stream of finds including ship components such as roof tiles and lead hull sheeting as well as finer items: sections of a bone flute, a blue game pawn and a statuette base. “These are prestige goods,” says Foley, “not the sort of thing you normally find on a wreck.”

Everyone was hoping for a headline-grabbing find, however, and on 8 September a shoebox-sized block of black metal, weighing nearly 30 kilograms, caused excitement. It was immediately dubbed the ship’s “black box”. But the metal turned out to be iron, probably a ballast weight dropped by Cousteau’s diving saucer.

A couple of days later, diver Alexandros Sotiriou uncovered the square end of a large object buried deep in the sand. He was unable to move it, but believed he saw the green glint of semi-precious bronze.

Now, as the team reaches the wreck site to investigate Sotiriou’s find, the excitement is palpable. As the first two divers descend, their colleagues and I crowd round a small screen on the boat, which shows a live video feed of progress underwater.

The divers wedge their scooter against a rock and use its propeller to create a water jet that pushes sand away. The pair disappear into a cloud of sediment, and later emerge with two long bars, each with a semicircular hole halfway down its length. The bars turn out to be lead, not bronze; the components of a large anchor. The team is quiet on the way back to harbour – this isn’t what the divers had hoped for. But it’s still a significant find, showing how deep the team must dig for larger items, and pinpointing the position of the ship’s bow. With the stern already located, Foley and Theodoulou calculate the vessel’s midpoint – a flat, featureless area dubbed “the meadow” – as the most likely place for its cargo.