Elgygytgyn Lake

Lake El'gygytgyn (Chukchi: Эльгыгытгын) is an impact crater lake located in the Chukotka Autonomous Okrug in northeast Siberia, about 150 km southeast of Chaunskaya Bay. It is drained to the southeast by the Enmybaam branch of the Belaya River. It is approximately 12 km in diameter and has a maximum depth of 174 m +/- 2m. The lake is centered within an impact crater with a rim diameter of 18 km that formed 3.6 million years ago during the Pliocene).

• http://en.wikipedia.org/wiki/Elgygytgyn Lake