Mackinac Island is located in Lake Huron, and the entire island is listed as a National Historic Landmark. Motorized vehicles were prohibited on the island in 1898 — with the exception of snowmobiles in winter and emergency vehicles — but visitors can travel via foot, bicycle or horse-drawn carriage. In fact, Michigan’s Lake Shore Road, which runs along the perimeter of Mackinac, is the only state highway that doesn’t allow cars, but it’s always busy — with clomping hooves and spinning wheels — on summer days.