Lake Superior the Soo Locks. Lake Superior is the largest freshwater lake in the world in area (if Lakes Michigan and Huron are taken separately; "see Lake Michigan–Huron"), and the third largest in volume, behind Lake Baikal in Siberia and Lake Tanganyika in East Africa. The Caspian Sea, while larger than Lake Superior in both surface area and volume, is brackish; though presently isolated, prehistorically the Caspian has been repeatedly connected to and isolated from the Mediterranean via the Black Sea. Lake Superior has a surface area of , which is approximately the size of South Carolina or Austria. It has a
Lake Baikal mean temperature varies from a winter minimum of to a summer maximum of . The region to the east of Lake Baikal is referred to as Transbaikalia, and the loosely defined region around the lake is sometimes known as simply Baikalia. Lake Baikal is in a rift valley, created by the Baikal Rift Zone, where the Earth's crust is slowly pulling apart. At long and wide, Lake Baikal has the largest surface area of any freshwater lake in Asia, at , and is the deepest lake in the world at . The bottom of the lake is below sea level,