William Mitchell State Park is a public recreation area covering 660 acres on the southwest side of Cadillac in northern lower Michigan. The state park is located between Lake Mitchell and Lake Cadillac. The historic Clam Lake Canal, approximately one-third of a mile in length, connects the two lakes and runs directly through the park. Dug in 1873 at the direction of city father George A. Mitchell, the canal allowed felled trees to be floated from Lake Mitchell to lumber mills on Lake Cadillac.