There is some debate about the Caspian Sea’s status as a lake. It is actually a remnant of the ancient Paratethys Sea, sandwiched between modern Anatolia and northern Asia, and part of the larger Tethys Ocean, which separated Africa and Eurasia. The salinity has decreased since becoming landlocked, and the Caspian Sea is now just one third as salty as the oceans. If indeed considered a lake, it is the world’s largest, nearly twice the size of its nearest competitor, Lake Superior. The energy industry is a major environmental threat, as it is both a strategic location for shipping and a major source of oil and natural gas. The Caspian Sea is bordered by Russia, Kazakhastan, Turkmenistan, Iran, and Azerbaijan, whose capital Baku is situated on the shore.
