The Caspian Sea is known to be the largest land enclosed body of water on Earth. Depending on where you go and whom you talk to, the sea is known as the world’s largest lake or the world’s largest sea. The sea covers an expanse 143, 244 square miles and has an impressive volume of 18,761 cubic miles.
The Caspian Sea is unique because it has no streams that flow out from it, so it is known as an endorheic body of water. The deepest portion of the Caspian that has been measured was more than 3,363 feet deep. While the water is salty, it has a salinity of just 1.2%, which is only about a third of most seawater. Those that first discovered the Caspian thought it was actually a sea because of the salinity.
The Caspian Sea was named after the Caspians and the is now known to be what is left of the Tethys Ocean, as is the Mediterranean and Black Seas. The Caspian became landlocked due to the drifting of continents about 5.5 million years ago. Today the Caspian is located on the coasts of Azerbaijan, Iran, Kazakhstan, Russia, and Turkmenistan. It is known to be the largest body of water in this region of the world, accounting for as much as 44% of the lacustrine waters of the world.
The Caspian Sea is divided into three distinct sections which s the Northern, the Middle, and the Southern Sea. The Northern is actually the Caspian shelf, and is known to be one of the shallowest areas, holding less than one percent of the total volume, with just five to six meters in depth on average. The Middle Caspian is where the waters start getting noticeably deeper, as deep as 190 meters and the Southern Sea is where the water is the deepest with depths of over 1,000 meters. It is the Middle and Southern Caspian Sea that account for most of the volume.
While there is not outflow from the Caspian Sea there are more than 130 inflow rivers, with the Volga River being the biggest. The Caspian is home to a few small islands, with most of them being located in the Northern Sea with all of the Caspian islands having an overall land area of 2,000 square kilometers.
Neighboring the Northern Caspian Sea is depression, which is a very low-lying region that is 27 meters below sea level. In addition, there is the Central Asian steppes that run along the northeast coast of the sea and the Caucasus mountains are along the western shore. The lands and the temperatures in these regions vary widely with low planes and mountainous regions, and therefore there is a large diversity of living things in and around the sea.