The Caspian Sea is the world’s largest inland body of water with an area of approximately 398 thousand square kilometers. Along with its large hydrocarbon reserves, the Caspian Sea is home to 90% of the world’s sturgeon stocks. More than 20 animals and about 20 plant species grow in the Caspian Sea listed in the Red Book. Until 1991, international relations regarding the Caspian Sea were regulated by only two documents. These are the 1921 Treaty between the Russian Soviet Federative Socialist Republic and Iran and the 1940 Trade and Navigation Treaty between the Union of Soviet Socialist Republics and Iran.
