An Anglo-Bulgarian expedition has announced that in 2017, they discovered the world’s oldest intact shipwreck. The expedition had been exploring the Black Sea off the Bulgarian coast when their ROV (remotely operated vehicle) came upon the wreck.

The well-preserved 23-metre-long vessel is thought to have been an ancient Greek trading ship and appears to have lain undisturbed at a depth of 2 kilometres for around 2,400 years. The ship’s design is similar to those depicted on ancient Greek pottery, such as the famous ‘Siren Vase’, which is on display in the British Museum.

The amazing preservation of artefacts in the Black Sea is due to a significant absence of oxygen in the water. The Black Sea happens to be the largest water body with a meromictic basin, which means the movement of water between the lower and upper layers of the sea is almost non-existent. This results in a considerable temperature difference between these layers along with making the lower layers free of oxygen and hence devoid of the creatures that destroy artefacts.