Lake Terkhiin Tsagaan Nuur, also known as the “White Lake”, is set within the Khangai mountains in central Mongolia, at an altitude of 2,060 metres. It measures 16 km wide by 20 km long, and its waters are exceptionally pure.
It lies within a protected area valued for its biodiversity, where several ecosystems coexist: taiga (boreal forest), mountain steppe, and wetlands home to a rich array of wildlife.
To the east of Lake Terkhiin Tsagaan Nuur lies the extinct crater of the Khorgo volcano, which gave rise to the lake: lava flows blocked the course of a river, creating a natural dam.
The Khorgo volcano sits at an altitude of 2,200 metres, its slopes covered in basalt, with a crater forming an almost perfect cone 200 metres in diameter and 100 metres deep.
Its last eruption was 8,000 years ago; it was the last active volcano in Mongolia.