Flat Rock, Idaho

Flat Rock (also known as Macks Inn) was a former unincorporated community along Henrys Fork in Fremont County, Idaho, United States, that is now part of the city of Island Park. The site of the former community in at .
Island Park is part of the Rexburg Micropolitan Statistical Area.
Transportation.
A U.S. Highway passes through the community, as did a former U.S. Highway: