Soudan is an unincorporated community in Breitung Township, St. Louis County, Minnesota, United States. The community is located immediately east of the city of Tower on Minn. Highway 169 / Minn. Highway 1. It is the home of McKinley Park, a state park and campground named in honor of the 25th President of the United States, William McKinley. The Soudan Underground Mine State Park is located nearby. The park contains the University of Minnesota's Soudan Underground Laboratory which houses detectors, including MINOS, over 700 meters below the surface of the Earth. Although it is unincorporated, Soudan has a post office, with the ZIP code of 55782.