You searched for: Place Mackinac State Forest; northwest corner of County Roads 415 and 422 (4.2 miles north of Highway M-28 at McMillan), just north and slightly above vast swamp of Tahquamenon River basin. Remove constraint Place: Mackinac State Forest; northwest corner of County Roads 415 and 422 (4.2 miles north of Highway M-28 at McMillan), just north and slightly above vast swamp of Tahquamenon River basin.