[1] The uninhabited island has a land area of 1.179 square kilometres (0.455 sq mi) or 117.87 hectares (291.3 acres).

The border between Wisconsin and Michigan was originally defined as "the most usual ship channel" into Green Bay from Lake Michigan, but commercial routes existed both to the north and south of the island, which led to a border dispute.

The island was re-colonized in 1895–6, when both a lifesaving station on the northeast corner and a set of range lights on the western side were built.

The lifesaving station operated from 1895 to 1991, before being moved to nearby Washington Island, while the range lights were automated in 1969 and remain[when?]

[6]The wreck of the Grape Shot is 0.18 miles (0.29 km) northwest of the lifesaving station in 8 feet (2.4 m) of water.