This historic mill is located in Minneopa State Park. It was built in 1864 by Louis Seppmann, an immigrant from Westphalia who worked as a stonemason. His creation is 32 feet high with a base diameter of 30 feet wide. Unfortunately, there is no entry to structures, although hopefully restorations will be completed in the future. It's near a waterfall trail and a bison drive-through. The park is open daily from 8 AM to 10 PM, although the bison drive is open 9 to 7 Thursday through Tuesday.