Open main menu

Boulder River (Sweet Grass County, Montana)

The Boulder River is a tributary of the Yellowstone River, approximately 60 mi (96 km) long, in south central Montana in the United States. It is one of two rivers named the Boulder River in Montana.

Boulder River
Boulderriver MT.jpg
A section of the upper Boulder River
CountryPark and Sweet Grass County, Montana
Physical characteristics
 ⁃ coordinates45°10′25″N 110°13′31″W / 45.17361°N 110.22528°W / 45.17361; -110.22528 (Boulder River)[1]
 ⁃ coordinates
45°51′10″N 109°55′25″W / 45.85278°N 109.92361°W / 45.85278; -109.92361 (Boulder River)Coordinates: 45°51′10″N 109°55′25″W / 45.85278°N 109.92361°W / 45.85278; -109.92361 (Boulder River)[1]
 ⁃ elevation
4,003 feet (1,220 m)[1]
Basin features
River systemYellowstone River

It rises in the Gallatin National Forest in the Absaroka Range in southern Park County. It flows north through mountainous canyons, a cataract under a natural bridge, and northwest in a widening valley past McLeod. It joins the Yellowstone at Big Timber. The landscape of the Boulder River and river valley has merited the filming of two movies: A River Runs Through It and The Horse Whisperer.[2]



The river is a popular destination for fly fishing. Other attractions in the valley include several church camps, a guest ranch, and several USFS campgrounds. The Forest Service also maintains several guard stations, trailheads, and picnic areas in the valley.[3]

Variant namesEdit

The Boulder River has also been known as: Rivers a Cross, Rivers across, and Rivers-across.[1] And, to distinguish it from the other Boulder River in Montana, it is sometimes called the "East Boulder River" (as it is east of the other) or the "Boulder Fork of the Yellowstone," parallel with the Clark's Fork of the Yellowstone as differentiated from the Clark's Fork River of Western Montana.

See alsoEdit


  1. ^ a b c d "Boulder River". Geographic Names Information System. United States Geological Survey.
  2. ^ "A River Runs Through It Trivia at the IMDb". Retrieved 2007-09-22.
  3. ^ "Map of USFS Big Timber Ranger District". Retrieved 2007-09-22.