Lake Vostok

Lake Vostok in Antarctica is the largest known subglacial lake, buried beneath 4,000 m of continental ice with water depths reaching 900 m. Located beneath the East Antarctic Ice Sheet near Russia's Vostok Station, Lake Vostok is the largest known subglacial lake in the world and ranks as the fourth-deepest lake overall, with water depths estimated at 900 m. The water body extends 250 km in length and 50 km in width, covering a surface area of roughly 12,500 km2 and containing an estimated volume of 5,400 km3. Completely isolated from Earth's atmosphere for an estimated 15 to 25 million years, Lake Vostok serves as an extreme planetary analogue for icy moons like Europa and Enceladus.