The salt is obtained from the saline lakes (limans) in the neighbourhood.
During the greater part of the year it is either dry or occupied in part by a string of saline lakes (limans or ilmens); but in spring when the streams swell which empty into it, the water flows in two opposite directions from the highest point (near Shara-Khulusun).
The western shore, from the delta of the Volga to the mouth of the Kuma, a distance of 170 m., is gashed by thousands of narrow channels or lagoons, termed limans, from 12 to 30 m.
More than this, the Caspian was also, it is pretty certain, at the same epoch, and later, in direct communication with the Sea of Azov, no doubt by way of the Manych depression; for in the limans or lagoons of the Black Sea many faunal species exist which are not only identical with species that are found in the Caspian, but also many which, though not exactly identical, are closely allied.
The network of shallow and still limans or "cut-offs" in the delta of the Volga and the shallow waters of the northern Caspian, freshened as these are by the water of the Volga, the Ural, the Kura and the Terek, is exceedingly favourable to the breeding of fish, and as a whole constitutes one of the most productive fishing grounds in the world.