The Bob Marshall Wilderness, an area located in Flathead and Lewis and Clark national forests in Montana, was created in the same year (1964) that the Wilderness Act became law. It had previously been set aside in 1941 as the South Fork, Pentagon, and Sun River Primitive Areas. The area encompasses a million acres (4,000 km2) and is one of the best-preserved ecosystems in the world. Known as "The Bob," it is the fifth-largest wilderness in the contiguous 48 states (Death Valley is the largest). In compliance with the 1964 Wilderness Act, no motorized or mechanical equipment (including bicycles or hang gliders) is permitted. Although camping and fishing are allowed with proper permit, the area is roadless, and logging and mining are prohibited. There are numerous U.S. Forest Service cabins in The Bob for use by Forest Service personnel. The Bob Marshall Wilderness Complex (which encompasses Bob Marshall, Scapegoat, and Great Bear Wildernesses) is a habitat for the grizzly bear, lynx, cougar, wolf, black bear, moose, elk and a variety of other birds, mammals, and plants.