How big is Lake Superior?

How Big Is Lake Superior? A Deep Dive Into the Largest Great Lake

Lake Superior is more than just a name—it’s a giant among lakes. Known for its vast size, frigid waters, and stunning shoreline, Lake Superior is the largest of North America’s five Great Lakes. But how big is it, really?

In this post, we’ll explore just how massive Lake Superior is, breaking it down by surface area, volume, depth, and more. If you’re a geography enthusiast, a traveler, or just curious about the natural world, read on—this freshwater giant is sure to impress.

Lake Superior at a Glance

Lake Superior is the largest freshwater lake in the world by surface area, and it dominates the Great Lakes system in both size and volume. Here's a snapshot of its incredible dimensions:

Surface Area: ~31,700 square miles (82,100 square kilometers)

Volume: ~2,900 cubic miles (12,100 cubic kilometers)

Length: ~350 miles (563 kilometers)

Width: ~160 miles (257 kilometers)

Maximum Depth: ~1,332 feet (406 meters)

These numbers alone make it clear—Lake Superior is a true freshwater ocean.

Surface Area: The Largest of Them All

Lake Superior covers approximately 31,700 square miles, making it the largest freshwater lake by surface area on Earth. To give you a comparison, it’s larger than the entire state of South Carolina or the country of Austria. The lake stretches across the U.S.-Canada border, touching Minnesota, Wisconsin, Michigan, and Ontario.

Volume: A Giant Reservoir of Fresh Water

In terms of volume, Lake Superior contains about 2,900 cubic miles of water. That’s over 3 quadrillion gallons—enough to cover all of North and South America with one foot of water. It also holds more water than all the other Great Lakes combined, plus three additional Lake Eries!

This massive volume means that Lake Superior holds 10% of the world’s surface fresh water.

Length and Width: Spanning Across States and Provinces

Length: At roughly 350 miles, Lake Superior stretches farther than the drive from Chicago to Detroit.

Width: At its widest, the lake spans 160 miles—so wide that the opposite shore often isn’t visible.

Its vast expanse can make it feel more like an inland sea than a lake.

Depth: Going Down Over 1,300 Feet

Lake Superior reaches a maximum depth of 1,332 feet (406 meters), which is deeper than the height of the Empire State Building. Its average depth is around 483 feet (147 meters), making it the deepest of all the Great Lakes. This depth contributes to its cold, crystal-clear waters that are often calm but can turn deadly during storms.

Final Thoughts: A True Freshwater Giant

Lake Superior isn’t just the largest of the Great Lakes—it’s one of the most impressive natural features on the planet. From its surface area to its depth and volume, every dimension of this lake is extraordinary.

So the next time you’re gazing at a map or planning a road trip through the Great Lakes region, take a moment to appreciate just how superior Lake Superior really is.