Four Great Lakes Border the U.S. Midwest

Of the five Laurentian Great Lakes, four directly border the Midwest region of the United States:

• Lake Superior — northern border of Minnesota, Wisconsin, Michigan (Upper Peninsula)
• Lake Michigan — entirely within U.S.; borders Wisconsin, Illinois, Indiana, Michigan
• Lake Huron — borders Michigan (eastern Upper Peninsula and "mitten")
• Lake Erie — borders Michigan, Ohio, Pennsylvania, New York

Lake Ontario lies farther northeast, bordering only New York State (and Ontario, Canada), and is generally considered part of the Northeast/Great Lakes region rather than the core Midwest.

These four lakes form the northern boundary of the Midwest, providing drinking water, shipping lanes, recreation, and climate moderation to tens of millions.