The Caspian Sea is the world’s largest body of water that is enclosed by land on all sides. It has a total area of about 386,400 square kilometers with the length of 1,200 kilometers and the width of 320 kilometers. Although the sea is considered the largest lake in the world, it is not the largest freshwater lake.
It can be classified as a brackish water body. The water in the sea is neither completely fresh water nor completely saltwater. The average salinity of its water is 1.2% and is about 1/3 of that of the oceans. Since the sea is completely enclosed by land, any water that enters the sea is either absorbed by the land or evaporates. This leads to salinization of its water. However, the sea is not uniformly saline. The Iranian coast is more saline than the northern part of the sea. The northern part contains a lot of fresh water due to the influx of fresh water. More than 100 rivers flow into the sea, including the Volga, Europe’s largest river. As most of these rivers contain fresh water, they make the northern part of the sea less salty.