The Stephen Mather Wilderness is a 634,614-acre protected backcountry in Washington’s North Cascade Range within the North Cascades National Park Complex, named for the first director of the National Park Service. Covering nearly all of North Cascades National Park and large parts of Ross Lake and Lake Chelan national recreation areas, it includes most of the complex’s roadless interior and adjoins other major wilderness areas, creating one of the state’s largest continuous protected mountain landscapes. Its rugged, often remote terrain supports recreation such as hiking, climbing, camping, wildlife watching, and hunting, while preserving extensive habitat for diverse mammals, birds, and fish.