 Northern side .png) Southern side Aerial photos of the island from late July 2020 | |
  St. Martin Island  St. Martin Island | |
| Geography | |
|---|---|
| Location | Lake Michigan |
| Coordinates | 45°29′52″N 86°46′13″W / 45.49778°N 86.77028°W |
| Highest elevation | 643 ft (196 m) |
| Administration | |
United States | |
| State | Michigan |
| County | Delta County |
| Township | Fairbanks Township |
St. Martin Island is located off the Garden Peninsula in Delta County in the U.S. state of Michigan. It is the southernmost island in Michigan that is part of a line of islands at the mouth of the bay of Green Bay and is part of the Niagara Escarpment.[1][2]