Historic Mill Creek, formerly known as Historic Mill Creek State Park and Historic Mill Creek Discovery Park, is a state park, nature preserve, and historic site in the United States state of Michigan. It is run by Mackinac State Historic Parks, the operating arm of the Mackinac Island State Park. 625 acres (2.5 km2) in size, the park is located 5 miles (8 km) southeast of Mackinaw City, Michigan on U.S. Highway 23.