The world's deepest lake — 20% of Earth's unfrozen fresh water, frozen glass highways, and endemic nerpa seals
Lake Baikal in Siberia is the world's oldest (25–30 million years), deepest (1,642m), and largest lake by volume — containing more fresh water than all the Great Lakes combined, approximately one-fifth of the world's unfrozen surface fresh water. The lake is extraordinarily transparent and biologically unique: 80% of its 3,500 species are found nowhere else on Earth, including the Baikal nerpa, the world's only freshwater seal. In winter, the 636km lake freezes to 1–2m of crystal-clear ice that visitors cross on foot, bicycle, and hovercraft — the ice bubbles from methane trapped below create…
Baikal appears in ancient Chinese chronicles as a great northern sea and featured in the accounts of Genghis Khan's campaigns. The Buryat people have lived on its shores for centuries, regarding it as sacred — 'the holy sea'. Russian Cossacks reached the lake in 1643, and the Trans-Siberian Railway along its southern shore was completed in 1905, including a remarkable section blasted through the Khamar-Daban mountains with 33 tunnels. The lake faces environmental pressure from a paper mill at Baikalsk (now closed) and tourism.