35°52′30″N 116°15′00″W / 35.87500°N 116.25000°W[1] Lake Tecopa is a former lake in Inyo County, southern California. It developed during the Miocene and the Pleistocene within a tectonic basin close to the border with Nevada. Fed by the Amargosa River and some neighbouring washes, it eventually culminated to a surface area of 235 square kilometres (91 sq mi) around 186,000 years ago and left sediments. Afterwards, the Amargosa River cut a gorge out of the lake and into Death Valley with its Lake Manly, draining the lake. The present-day towns of Shoshone, California and Tecopa, California lie within the basin of the former lake.