The following is a list of islands of Michigan. Michigan has the second longest coastline of any state after Alaska. Being bordered by four of the five Great Lakes—Erie, Huron, Michigan, and Superior—Michigan also has 64,980 inland lakes and ponds, as well as innumerable rivers, that may contain their own islands included in this list. The majority of the islands are within the Great Lakes. Other islands can also be found within other waterways of the Great Lake system, including Lake St. Clair, St. Clair River, Detroit River, and St. Marys River.
The largest of all the islands is Isle Royale in Lake Superior, which, in addition to its waters and other surrounding islands, is organized as Isle Royale National Park. Isle Royale itself is 206 square miles (530 km2). The most populated island is Grosse Ile with approximately 10,000 residents, located in the Detroit River about 10 miles (16 kilometres) south of Detroit. The majority of Michigan’s islands are uninhabited and very small. Some of these otherwise unusable islands have been used for the large number of Michigan’s lighthouses to aid in shipping throughout the Great Lakes, while others have been set aside as nature reserves. Many islands in Michigan have the same name, even some that are in the same municipality and body of water, such as Gull, Long, or Round islands.