An elliptical lake was identified in the Licancabur crater beneath the crater rim, with a length of and a depth of . Fed by snowfall, it is one of the highest lakes in the world. Based on its relative lack of salt deposits, in 1955 researchers postulated that the lake spilled through a notch in the crater's southwestern rim when the climate was wetter. Excess water now leaves through seepage, keeping salt levels low. There are other lakes (usually frozen) at similar altitudes in the Andes.