The Caspian Sea (Persian: Daryā-ye Māzandarān) in northern Iran is the world’s largest lake. Sefīd-rūd, Atrak and Aras rivers flow into the Caspian Sea. It is the natural habitat to over 350 species of fish. the
climate in on the coastal areas is temperate (humid subtropical) and there is rich plant life. the Caspian Sea is a major center of producing Cavier of world-class quality.