Interesting facts about Lake Superior

lake superior

Lake Superior, bounded by Ontario, Canada, and the U.S. state of Minnesota to the north, and the states of Wisconsin and Michigan to the south, is the largest of North America’s Great Lakes.

It is generally considered the largest freshwater lake in the world by surface area.

The surface area of Lake Superior is 82,170 square kilometers (31,700 square miles). That is 10% of all the Earth‘s fresh surface water

It is the world’s third-largest freshwater lake by volume (Lake Baikal in Siberia and Lake Tanganyika in East Africa contain more water) and the largest by volume in North America.

Lake Superior contains 12,100 cubic kilometers (2,900 cubic miles) of water. There is enough water in Lake Superior to cover the entire land mass of North and South America to a depth of 30 centimeters (12 inches).

Its average depth is 147 meters (483 feet) with a maximum depth of 406 meters (1,333 feet).

It has a maximum length of 560 kilometers (350 miles) and maximum width of 257 kilometers (160 miles).

lake superior from space

The average elevation of Lake Superior is about 183 meters (600 feet) above sea level.

The average underwater visibility of Lake Superior is 8.2 meters (27 feet), making it easily the cleanest and clearest of the Great Lakes. Underwater visibility in places reaches 30 meters 100 feet.

Lake Superior has been described as “the most oligotrophic lake in the world.”

The lake is fed by over 200 rivers. The largest include the Nipigon River, the St. Louis River, the Pigeon River, the Pic River, the White River, the Michipicoten River, the Bois Brule River and the Kaministiquia River.

The shoreline of the lake stretches 4,387 kilometers (2,726 miles) (including islands).

lake superior coastline

Lake Superior has over 400 islands, the largest of which is Isle Royale, with a size of 536 square kilometers (207 square miles).

Sliver Islet, a Lake Superior island off Ontario’s north shore, had been one of the richest silver mines in the world.

Lake Superior is one of the Earth’s youngest major features, at only about 10,000 years of age – dating to the last glacial retreat. By comparison, the Earth’s second largest lake (by surface area, and largest by volume), Lake Baikal in Russia, is 25 million years old.


Lake Superior is home to about 80 species of fish, including carp and varieties of trout, salmon and perch.

Lake Superior contains nearly 70 million diporeia (shrimplike creatures) with a total biomass greater than that of the human population in the entire Lake Superior basin.

Lake Superior is home to many species of birds, including varieties of hawks, eagles, loons, owls and woodpeckers. There is a small population of endangered whooping cranes on the lake’s north shore, one of only two crane species in North America. Migrating birds of prey funnel down Lake Superior’s north shore in great numbers each fall. On a single day, at Duluth’s Hawk Ridge, as many as 100,000 birds of prey might pass by.

lake superior eagle

Fifty-eight orchid species are native to the Lake Superior basin.

Among the scenic areas on the lake are: The Apostle Islands National Lakeshore [pic. below]; Isle Royale National Park; Pukaskwa National Park; Lake Superior Provincial Park; Grand Island National Recreation Area; Sleeping Giant (Ontario); and Pictured Rocks National Lakeshore.

apostle islands national lakeshore

The larger towns on Lake Superior include: The twin ports of Duluth, Minnesota and Superior, Wisconsin [pic.below]; Thunder Bay, Ontario; Marquette, Michigan; and the two cities of Sault Ste. Marie, in Michigan and in Ontario. Duluth, at the western tip of Lake Superior, is the most inland point on the Saint Lawrence Seaway and the most inland port in the world.

lake superior twin ports of duluth

The first people came to the Lake Superior region 10,000 years ago after the retreat of the glaciers in the last Ice Age.

The area was inhabited by Native Americans for many years before being explored in the mid-1600s by the French, including Samuel de Champlain (circa 1567-1635) and his scout, Étienne Brûlé (circa 1592-1632).

Lake Superior has been an important link in the Great Lakes Waterway, providing a route for the transportation of iron ore and other mined and manufactured materials.

Because of varying depths and unpredictable weather, Lake Superior and the other Great Lakes have been prone to maritime accidents. The last major shipwreck on Lake Superior was that of SS Edmund Fitzgerald, in 1975.

Waves of over 12 meters (40 feet) in height have been recorded on Lake Superior.

The average annual water temperature of Lake Superior is 4.4ºC (40ºF). It only very rarely freezes over completely, and then usually just for hours. The last complete freezing of Lake Superior occurred in 1979, although the lake was almost completely frozen over in 2014.