Apple River has been flowing through the driftless region of northwest Illinois for centuries, cutting through the limestone, dolomite, and shale deposits to carve Apple River Canyon and create the cliffs that rise out of the water. The park has five trails that wind through the woods for several miles and offers 49 class C campsites. Apple River provides a variety of fishing options including smallmouth bass, sunfish, crappie, and carp. It is also stocked with keeper size trout during trout fishing seasons. Other sites in the Apple River Canyon complex also offer hunting.