Caspian Sea reaches to Russia from the north and to Iran from the south. Turkmenistan and Kazakhstan countries are in its east and it is co-border with Republic of Azerbaijan and other parts of the Russia from the west.
It is about sixty million years that Caspian Sea has being restricted among the lands. Before that time, it was considered as a part of Tethys Ocean that linked Pacific and Atlantic Oceans to each other. It was later separated from Tethys. Currently, Caspian Sea flows into free waters through Volga river.
The length of this semi-salty sea is approximately 1200 kilometers and its width is 320 kilometers. It has 1000 meters of depth in its deepest point. The value of this lake increases due to its oil and gas sources so that it is ranked third in the world because of its gas and oil reserves.
The extraction of oil and gas by the neighboring countries has led to the water pollution and done a great deal of damage to some biological species of the sea.
The caviar of Caspian Sea is highly famous so that much of caviar in the world comes from this lake. In addition, four hundred species and subspecies of fish live in this sea.
A historical viewpoint says that Khazar is the name of an ancient tribe who was desert ranger in Caucasus and attacked to Iran many times. This occurred in time of Sassanid empire and they always failed from Sassanid army. That is why some believe that the global names of Caspian Sea or Mazandaran Sea are more proper than Khazar for this lake. Nevertheless, 21st of Mordad is called the national day of Khazar Sea.
The beautiful beach of Mazandaran is one of the popular tourism attractions of Iran that has 740 kilometers. You can easily access to the Caspian Sea through different cities in Mazandaran, Gilan and Golestan provinces. Water Park of Ramsar, Gissom Coast, Ashuradeh Island, Pardis Coast beach and Tuska Sara Beach are among the beautiful beaches of Caspian Sea.