Kura (kŏräˈ) [key], ancient Cyrus, Georgian Mktvari, Azeri Kür, river, c.950 mi (1,530 km) long, the chief river of Georgia and Azerbaijan. It rises in NE Turkey, NW of Kars, and flows NE into Georgia, then SE, parallel to the Caucasus Mts., to the Caspian Sea. There are hydroelectric plants on the river near Tbilisi, Georgia, and Mingachevir (Mingechaur), Azerbaijan; the extensive reservoir at Mingachevir is also used for irrigation. The lower Kura River, joined by the Aras River, its chief tributary, flows through an irrigated plain that extends into NW Iran. Cotton is the chief industrial crop of the region, which lies partly below sea level. The Kura is navigable c.300 mi (480 km) upstream.