CAS'PIAN SEA. Lying on the boundary between Europe and Asia, the Caspian Sea is the largest salt lake and the greatest interior body of water in the world. It is about 700 miles long and varies in breadth from 130 to 270 miles; its area is about five times that of Lake Superior. With the exception of Persia on the south, it is entirely surrounded by terri tory which formerly belonged to the Russian Empire.
The great oil wells near Baku and the great fisheries at the river mouths give the Caspian its chief claim to commercial importance. Under settled conditions Baku, situated on the Apsheron peninsula, is the greatest oil center in Europe. Few other lakes or seas are so richly stocked with fish — sturgeon, salmon, carp, perch, etc. Large quantities of caviar, which is regarded as a great delicacy, are made from the eggs of the sturgeon.
In ancient days the Caspian was part of a much larger sea, which may have joined the Sea of Azof (a bay of the Black Sea) on the west, and in cluded the Sea of Aral on the east.
Today, however, the surface of the Caspian is 85 feet below the Black Sea and 240 feet below the level of the Sea of Aral. In the southern part it is very deep, reaching a maxi mum of 3,000 feet, but in the north there are numerous shoals. One peculiarity of the sea bottom is a ridge which seems to be a continuation of the Caucasus Mountains, though under the surface of the water.
The Caspian has no outlet, and consequently is a salt lake, though it is less salt than the ocean. The water is bitter and yellowish in color. The Caspian is fed by a number of rivers, among which are the Volga (one of the most important rivers in Russia), the Ural, the Terek, and the Kur. By a system of canals connecting the Volga, it is possible to reach the Black Sea on the west and the Baltic and White seas far to the north. The chief Caspian ports are Astrakhan, Baku, Derbend, and Astrabad, the latter being in Persia. Steamboats ply regularly on the Caspian and on several of its tributary rivers. On the south a low flat plain, from 15 to 20 miles in width, leads to the lofty range of the Elburz Mountains, while the north is bordered by great steppes. The Caucasus Mountains lie to the west, and the desert Trans caspian territory to the east.