Tilicho lake trek is one of the unexplored treks at an altitude of 4,949 m high in the Annapurna range of the Himalayas in Nepal. Another source lists Lake Tilicho as being 4,919 meters high.

Mountain lakes are known to geographers as tarns if they are caused by glacial activity. Tarns are found mostly in the upper reaches of the Himalaya, above 5,500 meters. Due to the extremely inhospitable surrounding terrain and the difficulties associated with reaching the area, this lake is rarely visited by trekkers.
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