Mongold Day Use area is 1.5 miles west of Detroit Lake State Park. It's the only public boat launch facility on the lake featuring a swimming area, grass beach, picnic facilities and restrooms. Mongold is a year-round fee area.
Mongold has 58 single car parking spaces and three fully-accessible parking spaces near the swimming area, and another 25 single car parking spaces at the top of the parking lot. There are 120 vehicle/trailer parking spaces, and three that are accessible to people with disabilities.
Overnight parking at Mongold is permitted only when the visitor is camping on Piety Island.