The Bob Marshall Wilderness, the 1,009,356-acre centerpiece of a complex including Great Bear and Scapegoat wilderness areas, was designated in 1964, and named for forester, conservationist, and Wilderness Society founder Bob Marshall (1901–1939).
"The Bob" is one of the most expansive untouched ecosystems in the world, and hosts the densest population of American grizzly bears outside of Alaska.
The Bob's signatured feature is the Chinese Wall, a 1,000-foot-high escarpment running 22 miles up the 60 miles of Rocky Mountain spine encompassed by the wilderness. The north and south forks of the Sun River and the middle and south forks of the Flathead also rise in the Bob. Rafting the Flathead's middle fork is possible for those willing to pack or fly in, and is best in late summer. The Flathead's middle fork offers some of the state's wildest whitewater, especially during peak midsummer flows. Rafters generally put in at Schafer—the only landing field in the complex that's publicly accessible.
Early rifle season starts mid-September, and hunters show the fertile wilderness heavy use. More than 50 professional outfitters and guides operate in the wilderness.
For hikers and horseback riders, over 1,000 miles of trails dig deep into the Bob proper. The wilderness can be accessed via U.S. Highway 2 to the north, U.S. 89 and 287 to the east, and Montana Highway 200 and 83 to the south and west. Towns with services bordering the wilderness include Swan Lake, Seeley Lake, Lincoln and Hungry Horse to the west, and Augusta, Choteau and Dupuyer to the east.