Lake — World’s Second-Biggest (Surface Area)

The second-biggest lake in the world in terms of surface area is Lake Superior, which is located on the border between Canada and the United States. It covers an area of 31,820 sq mi (82,414 sq km). Aside from being the second-biggest in terms of area, it is the biggest freshwater lake in the world by area. It is also the world’s third largest in terms of water volume.

One of the Great Lakes of North America (the others being Lake Erie, Lake Huron, Lake Michigan, and Lake Ontario), it was originally formed by glacial action at the end of the last ice age between 10,000 and 11,000 years ago. The actual shaping of the lake took place gradually over the past 2.5 million years.

What is considered the biggest lake in the world by area is the Caspian Sea. Despite its name, it is considered a salt-water “oceanic” lake since it is landlocked, has no outflows, and is fed by rivers. It covers an area of 143,244 sq mi (371,000 sq km).


Surface Area31,820 sq mi (82,414 sq km)
Volume3-quadrillion gallons
Average Depth483 ft (147 m)
Shoreline Length1,826 mi (2,938 km)
Primary Inflow Sources (rivers)Nipigon, St. Louis, Pigeon, Kaministikwia, Pic, White, Michipicoten, Sturgeon, Tahquamenon
Primary OutflowSt. Mary's River into Lake Huron
Average Surface ElevationAbout 602 ft (183 m)
(Sources: NOAA, Minnesota Sea Grant, Encyclopedia Britannica)