The North Cascades National Park Complex consists of three units which make up Stephen Mather Wilderness: 505,000-acre (204,366 ha) North Cascades National Park, which boasts 504,614 acres (204,210 ha) acres of designated wilderness; 117,600-acre (47,591 ha) Ross Lake National Recreation Area, a slim piece of land just east of the park that has 74,000 acres (29,947 ha) acres of designated wilderness; and 62,000-acre (25,091 ha) Lake Chelan National Recreation Area, at the southeast corner of the park, with 56,000 acres (22,662 ha) of designated wilderness.[2]
Common recreational activities in the Stephen Mather Wilderness include backpacking, camping, wildlife watching, climbing, and hunting. There are some 390 miles (628 km) of trails in the wilderness, include the Pacific Crest Trail, which crosses the southeastern corner of the park for about 13 miles (21 km). Much of the area can only be reached by multiday hikes, often combined with mountaineering, through remote, trailless territory.[2]