The Evolution of Michigan's Legal Boundaries
Few published maps show Michigan’s true boundary. Michigan’s legal boundary does not stop at the shoreline of the four Great Lakes that encircle it, but extends into them to include almost 40,000 square miles of water, comprising 40% of Michigan’s area. Most maps of Michigan show only the upper and lower peninsulas plus a few major islands. The U.S. Geological Survey, however, recognizes 420 named islands in the Great Lakes belonging to Michigan. Michigan's legal boundary was established in a 1836 Act prior to attaining statehood on January 26, 1837. Since statehood, eight challenges to the boundary have resulted in adjustments that relinquished territory to Minnesota, Wisconsin, and Ohio, but gained territory from Canada.