The Southwest Couloir is one of the best-known alpine routes on Granite Peak and is documented in standard Beartooth climbing references. It is a serious mountaineering line rather than a hiking route, with steep snow, mixed terrain, and route-finding challenges. Conditions vary widely by season, and the couloir can involve rockfall or loose rock when snow is sparse. The route typically requires an early start and competent movement on steep alpine terrain. It is generally considered a classic way to climb the highest peak in Montana. Exact time, gain, and length figures are not consistently documented in the sources I can verify, so they are omitted.
Route Outline
Trailhead or approach basin -> Granite Peak cirque
Climb the Southwest Couloir toward the upper mountain
Exit onto the summit ridge/upper face
Follow the ridge to the summit
Descend by the same route or an established descent line
