– Areas—Madeline, Washington: WorldIslandInfo.com measurements from US Geological Survey maps.
– Areas—French Island: WorldIslandInfo.com measurements from DeLorme, Wisconsin Atlas and Gazetteer (Yarmouth, ME: DeLorme, 2008, 74.
– Populations—French Island, Doty Island: American FactFinder, U.S. Census Bureau.
– Populations—Washington Island: “Washington Island 2008” map, Washington Island Chamber of Commerce, 2008.
– Oak Island height—“Wisconsin, Michigan and the Great Lakes” map, National Geographic Society, 1973; “Great Lakes Water Levels (Feet),” United Stated Army Corps of Engineers, September 2, 2008.
– Outer Island location—“Wisconsin, Michigan and the Great Lakes” map, National Geographic Society, 1973.
– Stockton Island area—George J. Kraft et al., Assessment of Coastal Water Resources and Watershed Conditions at Apostle Islands National Lakeshore (Wisconsin), Natural Resource Technical Report NPS/NRWRD/NRTR-2007/367, National Park Service, U.S. Department of the Interior, 51.
Wisconsin Island Superlatives
For a non-coastal state, Wisconsin has a substantial endowment of islands: the Ice Ages have left the state with long Great Lakes shorelines, and lakes by the thousands. Wisconsin’s portion of the Mississippi River is also home to myriad islands, including one of the most heavily populated river islands in the US.
Largest island, largest lake island
The largest island in Wisconsin is Madeline Island, at the north tip of the state in Lake Superior, with an area of 24 sq mi / 62 sq km. It is also the state’s largest lake island, and the 17th largest island in the Great Lakes. Washington Island, in Lake Michigan, is just slightly smaller.
Wisconsin’s largest river island is French Island, a 4.3 sq mi / 11 sq km island in the Mississippi just north of La Crosse.
The largest island on another island in Wisconsin is the largest of four islands in Mackaysee Lake on Chambers Island in Green Bay.
About 10,000 people live on islands in the state; of these, about 1,000 live on unbridged islands.
The most populous island in Wisconsin is French Island, in the Mississippi at La Crosse, with 4,505 inhabitants as of the 2000 census. Doty Island, in the Fox River and Lake Winnebago at Neenah and Menasha, is the second-most populous, with 3,846 as of 2000. French Island is also the state’s most populous river island.
Most populous unbridged island
The most populous unbridged island is Washington Island, with about 680 permanent inhabitants. Washington is also Wisconsin’s most populous lake island.
Largest uninhabited island
Wisconsin’s largest uninhabited island is Stockton Island in the Apostle Islands, at 15.5 sq mi / 40.0 sq km.
Wisconsin’s tallest island is Oak Island, in the Apostle Islands: it rises about 513 feet / 156 meters from Lake Superior. Oak is also the tallest lake island in the state.
Most isolated island
Outer Island, in the Apostle Islands in Lake Superior, is about 15 miles / 25 km from the mainland.
Copyright 1995-2008 Joshua Calder
Contact Joshua Calder at calder.josh[at]gmail.com with questions or suggestions.
island geography / biggest island