Kura (Caspian Sea) emptying into the Caspian Sea at Neftçala. Most of the Kura River runs in the broad and deep valley between the Greater Caucasus and Lesser Caucasus mountains, and the major tributary, the Aras, drains most of the southern Caucasus and the mountain ranges of the extreme northern Middle East. The entirety of Armenia and most of Azerbaijan are drained by the Kura River, but the Kura does not pass through Armenia at all. Also in the Kura watershed are Turkey, Georgia, and a bit of northern Iran. Most of the elevation change in the river occurs within the first .
Caspian Sea of around 149,200 square miles (386,400 square km)— bigger than the region of Japan—and its surface lies somewhere in the range of 90 feet (27 meters) below sea level. The sea bed in the southern part reaches as low as 1,023 m (3,356 ft) below sea level, which is the second lowest natural depression on earth after Lake Baikal (−1,180 m, −3,871 ft). The ancient inhabitants of its coast perceived the Caspian Sea as an ocean, probably because of its saltiness and large size. The sea has a surface area of 371,000 km (143,200 sq mi) (not including the detached