Porcupine Mountains Wilderness State Park is 15 miles west of Ontonagon in Michigan's Upper Peninsula. The park's 60,000 acres are one of the few remaining large wilderness areas in the Midwest. Towering virgin timber, secluded lakes, and miles of wild rivers and streams make a visit to the "Porkies" a trip to remember. As Michigan's largest state park, planning your trip may require the use of various maps.