It is enclosed in the Andes mountain range, at 630 m (2,070 feet) above mean sea level.

The area around the lake is mostly uninhabited, except for the city of San Martín de los Andes on its northeastern coast.

As the northernmost[1] lake on the eastern side of Andes that drains to the Pacific the lake and its catchment basin were claimed by Chile until 1902 based on an interpretation of the Boundary treaty of 1881 between Chile and Argentina.

[2] The lake, along with the smaller lake nearby, Lolog, has some sacred significance for the Mapuche people, as it features in their oral tradition as part of a creation myth.

[1] The dominant species of plankton in the lake is Aphanocapsa elachista.