Khövsgöl nuur is located in the northwest of Mongolia near the border to Russia, at the foot of the eastern Sayan Mountains. It is 1,645 m above sea level, 136 km long and 262 m deep. It is the second-most voluminous freshwater lake in Asia.The surface of the lake freezes over completely in winter. The ice cover gets strong enough to carry heavy trucks.Khövsgöl is one of seventeen ancient lakes worldwide more than 2 million years old and the most pristine (apart from Lake Vostok).