The Caspian Sea is the largest enclosed body of water onEarthby area, variously classed as the world's largestlakeor a full-fledgedsea. It has a surface area of 371,000square kilometers (143,244 sq mi) and a volume of 78,200cubic kilometers (18,761 cu mi).<ref name=LakeNet">Lake Profile: Caspian Sea. LakeNet. It is anendorheicbody of water, and lies between the southern areas of theRussian Federationand northernIran. It has a maximum depth of about 1025 meters (3,363 ft). It is called a sea because when the Romans first arrived there, they tasted the water and found it to be salty.