Sunken Venetian island raised to reveal unique 13th-century galley

Italian archaeologists will this week examine for the first time a wooden galley which they hope will reveal the secrets of the master shipmakers who helped the Venetian republic, La Serenissima, to dominate the Mediterranean for centuries. To bring the remarkably preserved vessel to the surface has involved raising a tiny island submerged under the Venice lagoon waters since the 1500s. The galley, which dates from the 13th century and was powered by 250 oarsmen, is the only one of its kind ever recovered.

Italian archaeologists will this week examine for the first time a wooden galley which they hope will reveal the secrets of the master shipmakers who helped the Venetian republic, La Serenissima, to dominate the Mediterranean for centuries. To bring the remarkably preserved vessel to the surface has involved raising a tiny island submerged under the Venice lagoon waters since the 1500s. The galley, which dates from the 13th century and was powered by 250 oarsmen, is the only one of its kind ever recovered.

Chief archaeologist Marco D'Agostino discovered it in 1997 near the sunken island of San Marco di Boccalama in the south-west of the lagoon. Mr D'Agostino, an experienced underwater archaeologist, and a technician were checking that maintenance work on the petrol-tanker canals were not disturbing the lagoon bed when they spotted the remains of a vessel unlike anything they had ever come across.

"Until now all we have had to go on in understanding the wizardry of the proti (shipmakers) were sketches and manuscripts. Now we are going to be able to see first hand what the vessels looked like, how they designed it and perhaps understand why it gave the Venetians supremacy," said Mr D'Agostino.

The galleys were initially rowed by free men but later prisoners and slaves were used. The vessels had long narrow hulls, with sails to give extra speed. They were used to transport precious merchandise and as warships. The Venetians were the first to put the nimble boats to use to dominate the seas and ward off pirates, but the rival Genoese republic, the Catalans and the Ottomans later adopted the agile craft.

"The fact that none has ever been found is because they did not have a heavy cargo like amphorae that would force them down to the seabed. The galleys either carried men or relatively light and precious cargo, so once sunk they disintegrated quickly," explained Mr D'Agostino.

The 124ft x 16ft galley coming to light in Venice is an exception. Its survival is linked to the history of San Marco di Boccalama, first detected in the late Sixties. It is one of many land forms which over the centuries have been swallowed up by the lagoon. In the early 1300s the monks on the island realised it was sinking fast and sought desperate remedies. A document from 1328 records that a galley and a barge were filled with silt, sunk and anchored to wooden piles to form a barrier against the waves. The solution worked for a while. But by 1348, when Venice was struck by a great plague, the monks had left and the island was used as a mass graveyard. Sporadic discoveries of skeletons and other bones have punctuated the recovery of the galley and barge. The flat-bottomed barge, 80ft x 20ft, is of less interest to historians. Such craft were widely used for river and lagoon transport.

The complex salvage operation is expected to cost £300m. It involved sealing off the island with a 50ft-high steel barriers, then pumping water out of the sealed area. Slowly the island, previously seven feet under water, emerged, and with it the two boats. While they were still under water, divers emptied out the silt from inside the vessels.

This week will see the most exciting phase when wraps are removed and archaeologists can examine the galley. The silt filling has preserved the woodwork perfectly and the craft will have to be constantly doused with salt water to avoid it crumbling on exposure to the air.

However, the contact with the atmosphere will be brief. Once the vessels have been photographed and examined in detail, they and the island are likely to be submerged again.