It looks like the rib cage of a large marine mammal, whose bones turned black as it was fossilised. The wreck was discovered in May during a dig in Antibes, on the French Riviera, prior to construction of a car park on the site of the Roman port of Antipolis. Archaeologists have gradually uncovered a 15-metre length of hull and structural timbers, in "exceptional" condition, according to Giulia Boetto, a specialist in ship design at Aix-Marseille University who is involved in the dig. Saw and adze marks are still visible on the wood. Luckily the ground in which it was...