Thompson’s Harbor is a Michigan State Park that encompasses over 5000 acres of undeveloped beach dunes, upland and marsh. It includes unique areas of Lake Huron Sand Dunes and is home to the Dwarf Lake Iris, a rare and endangered plant.

Three trails can be hiked, ranging from 1.4 to 2.6 miles and covering 7.5 miles of Lake Huron Shoreline. Park at the trailhead off of U.S. 23, about 3 miles north of County Road 638.