General Carrera Lake (Chilean part, officially renamed in 1959) or Lake Buenos Aires (Argentine part) is a deep lake located in Patagonia and shared by Argentina and Chile. Both names are internationally accepted, while the autochthonous name of the lake is Chelenko, which means "stormy waters" in Aonikenk. Another historical name is Coluguape from Mapuche, a derivative of this name is applied to Colhué Huapí Lake after Argentine explorer Francisco Moreno reached this lake in 1876 conflating it with Coluguape (General Carrera Lake).
The lake is of glacial origin and is surrounded by the Andes mountain range. The lake drains to the Pacific Ocean on the west through the Baker River. During the last glaciation the lake drained to the Atlantic through Deseado River.