The Kuma–Manych Depression (Russian: Кумо–Манычская впадина, Kumo–Manychskaya vpadina), is a geological depression in southwestern Russia that separates the Russian Plain (north) from the Fore-Caucasus (south). It is named after Kuma and Manych rivers.
It is sometimes regarded as a definition for the natural boundary between Europe and Asia, although most modern sources use the Greater Caucasus watershed instead. The proposal of the Kuma–Manych Depression as a continental boundary is originally due to Philip Johan von Strahlenberg (1725), and was officially endorsed by Peter II of Russia in 1730.
Coordinates: 45°42′54″N 44°06′18″E / 45.71500°N 44.10500°E