Fort Holmes is a fortified earthen redoubt located on the highest point of Mackinac Island.

[3] The British named the redoubt Fort George and reinforced it with cannon, a blockhouse, and a magazine for gunpowder and other munitions.

[3] When United States armed forces reoccupied Mackinac Island in 1815 under the terms of the Treaty of Ghent, they took possession of Fort George.

[4] As of 1984[update], however, most of the reconstructed buildings of Fort Holmes had again disappeared, except for the redoubt's earthen walls.

[3] In 2015 the Mackinac Island State Park completed a second reconstruction of Fort Holmes that resumes the appearance that the redoubt had in 1817.