This route is the shortest approach up Johnstone Peak, but is certainly not the most scenic.
Drive 4 miles northeast of Ketchum to the Corral Creek Road, an improved and well marked dirt road leading to the east. Follow Corral Creek Road uphill 1.5 miles until reaching the first major canyon to split off to the south. This is Uncle Johns Gulch. The TOPO map shows this road continuing up the gulch for a while, it doesnt. The road quickly dies out shortly after turning onto it, begin here.
Hike up Uncle Johns Gulch in the depths of a thick spruce forest on a faint trail. After about a mile and half the trail fades in a large debris field beneath the magnanimous western face of Johnstone Peak. Two options greet you at this point that lead you to the southwestern ridge of Johnstone Peak..
Option 1: If ascending in spring and an avalanche has swept the face before you (90% of a probablilty), head towards the remains of the avalanche path and begin ascending on the snow field. Continue up the snow field until it dissipates around 8600-8800'.
NOTE: The snow field described above does not require an ice axe or crampons...
From here, turn east to gain Johnstone's southwest ridge. On gaining the ridge, sections of class 3 climbing can be avoided by deviating through the gullies in between.
Option 2: From the large debris field, make your way in a more southeasterly direction toward the saddle at 8,600' between Johnstone Peak and Pt. 8,833.
Once on the southwestern ridge, it is an obstacle free walk to the summit.
There is no techinicality on this route up Johnstone Peak whatsoever....However, I met some moose on the way down so some mace may not be a bad idea.
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