Borah Peak

Borah Peak ranks No. 27 among the 57 ultra-prominent peaks in the contiguous United States, rising 12,662 feet in the Lost River Range of Idaho with 5,990 feet of clean prominence. It is Idaho's highest mountain and the high point of the Lost River Range. Most hikers and scramblers ascend the Southwest Ridge for roughly 8 to 8.2 miles round-trip with about 5,200 to 5,300 feet of gain, including the exposed Class 3 Chickenout Ridge crux.

The peak is best known for Chickenout Ridge, an exposed Class 3 crux between 11,200 and 11,400 feet where the psychological exposure often exceeds the actual technical difficulty. The ridge is narrow, features loose rock, and drops steeply on the north flank. Many experienced climbers choose to turn back here despite solid route-finding skills. The October 1983 Borah Peak earthquake uplifted the Lost River fault by several feet; modern published elevations commonly cite 12,662 feet, though topographic surveys have some variation.

Southwest Ridge

The Southwest Ridge is the standard and most-traveled route to the summit. The climb begins at Borah Peak Trailhead at 7,400 feet and gains approximately 5,200 to 5,300 feet over roughly 8 to 8.2 miles round-trip. The lower section ascends steep sagebrush-covered slopes on an established trail, reaching open alpine terrain by mid-elevation. From there, the route follows the southwest ridge spine upward through increasingly exposed scrambling terrain.

The Chickenout Ridge crux occupies the narrow section between 11,200 and 11,400 feet. This Class 3 section requires solid scrambling technique over loose rock, careful footwork, and comfort with significant exposure. The north flank drops steeply toward the basin below, creating serious exposure. Parties must navigate route variations around the ridge crest, all of which demand careful attention to foot placement and route-finding in order to avoid rockfall hazard to climbers below. Above the crux, parties continue on scree and talus slopes to reach the bare rock summit, which offers expansive views across the Lost River Range, Lemhi Mountains, and surrounding peaks to the south and east.

Descent follows the same route; the Chickenout Ridge presents the same technical challenge on the way down. Early-season snow may make glissading appealing but adds significant risk; downclimbing the Class 3 section is the safer choice.

Key Landmarks

• Chickenout Ridge (11,200–11,400 ft) — exposed Class 3 scrambling with serious exposure on the north flank
• Summit (12,662 ft) — bare rock with expansive alpine views

July through early September offers the most stable and snow-free conditions. Late June can be snow-dependent. September brings shorter days and colder conditions, with snow possible later in the month. May and June involve snow; early-season ascents require winter mountaineering competency. Downclimbing is safer than glissading on early-season snow. The sustained elevation gain of 5,200 to 5,300 feet demands strong fitness. Class 3 scrambling requires comfort with hands-and-feet movement on loose, exposed rock. Mountain navigation in poor visibility and sound turnaround discipline are essential. Ropes and climbing protection are not required in dry summer conditions. Snow-covered ascents, common in May and June and possible into July or again in September, are significantly more technical. Steep snowfields, potential avalanche terrain on the north face, and narrow snow ridges require an ice axe, crampons, and solid winter mountaineering skills with self-arrest ability. Afternoon thunderstorm development is typical July through August; the exposed ridge presents extreme lightning risk. The rapid ascent to 12,662 feet may cause altitude sickness; adequate acclimatization is important. Despite its Class 3 technical grade, Borah ranks among the most challenging state highpoints due to sustained elevation gain, altitude, exposure, and the mental discipline required to turn back if conditions warrant.