Lake Baikal is the world’s deepest lake. It is located in Siberia, Russia. It is 5,387 feet (1,642 metres) deep, and its bottom is 3,893 feet (1,187 metres) below the sea-level. It is also the world’s largest freshwater lake. It contains 20 per cent of the world’s total unfrozen freshwater reserve. There are more than 30 rocky islands in Lake Baikal. One of them is the world’s second largest island in a lake, Olkhon.