Caspian Sea
The wide and endorheic Caspian Sea has a north–south orientation and its main freshwater inflow, the Volga River, enters at the shallow north end. Two deep basins occupy its central and southern areas. These facts lead to horizontal differences in temperature, salinity, and ecology. The Caspian Sea spreads out over nearly 750 miles (1,200 km) from north to south, with an average width of 200 miles (320 km). It covers a region of around 149,200 square miles (386,400 square km)—bigger than the region of Japan—and its surface is about 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.
Caspian Sea
, negotiations related to the demarcation of the Caspian Sea had been going on for nearly a decade among the states bordering the Caspian – Azerbaijan, Russia, Kazakhstan, Turkmenistan, and Iran. The status of the Caspian Sea is the key problem. Access to mineral resources (oil and natural gas), access for fishing, and access to international waters (through Russia's Volga river and the canals connecting it to the Black Sea and Baltic Sea) all depend upon the outcomes of negotiations. Access to the Volga River is particularly important for the landlocked states of Azerbaijan, Kazakhstan, and Turkmenistan. This concerns Russia, because the potential traffic would use its inland waterways. If a body of water is labelled as a sea, then there would be some precedents and international treaties obliging the granting of access permits to foreign vessels. If a body of water is labelled merely as a lake, then there are no such obligations. Environmental issues are also somewhat connected to the status and borders issue.