Minnesota’s license plate reads “Land of 10,000 Lakes,” but it really has almost 12,000 lakes.
And with more than 15,000 lakes, Wisconsin, especially the northern part, is a water lover’s paradise. Lake Winnebago is the largest, covering 215 square miles (559 sq km).
Like so many other lakes in this part of the world, these lakes were formed when the mile-thick glaciers that once covered the northern part of North America carved out parts of the Earth that later became lake beds.
Glaciers are huge sheets of ice that pick up huge amounts of rock and debris as they move.
It is these materials that erode the land underneath the glacier.
Between 8,000 and 15,000 years ago, during the last Ice Age, glaciers created most of the Earth’s lakes and many other dramatic geological features, including the Grand Teton Mountains in Wyoming.
Glaciers extended over much of North America during the last Ice Age.