Lake Vostok

Lake Vostok is a large subglacial lake that rests beneath in. Sitting approximately 3500 meters above sea level, the lake rests 4000 meters beneath Antarctica's surface.

A core ice sample was recovered from the lake in 2012, and research will soon begin to provide a paleoclimatic record going back 400,000 years. Abstergo Industries hopes that the research will provide insight into First Civilization life.

Reference

 * Assassin's Creed IV: Black Flag