Caspian Sea

Caspian Sea
Between the southern areas of the Russian Federation and northern Iran lies the largest enclosed body of water on Earth. It's an endorheic lake with salty water (salinity of approximately 1.2%) that was landlocked due to continental drift 5.5 million years ago. An ancient remnant of the Tethys Ocean (just like the Black Sea or the Mediterranean Sea), it is the third deepest lake in the world, going down to 3,363 feet.
Fauna in the Caspian basin is very rich: great numbers of sturgeon (that's where you get the great caviar); the Caspian seal; and some fish endemic to the Caspian Sea like the Kkturn (Caspian white fish), Caspian roach, Caspian bream and an array of rare species of salmon are only to be found in that area.
The Caspian Sea is very rich in energy resources like oil and gas deposits, which have been tapped since the 10th century. These days, the oil in the Caspian basin is supposed to be worth $12 trillion