From the Cliff Lake trailhead, follow the trail up a short and gentle ridge to a small and beautiful (in the spring) bench filled with Glacier Lillies, little rivelettes and miniature waterfalls. This area is extremely fragile so please take care to stay on the used path. At just less than a mile, you'll reach rocky slabs at Milwaukee Pass. Chicago Peak is directly to the west of the pass and Copper Lake is below and to the north. Continue along slabs at the same elevation towards the east and reach the short rocky slope above Cliff Lake at 1 mile from the trailhead (6,700 feet). Follow the faint path around the south side of the lake (counter clockwise) and up over a short hill at its east end. Maintaining about 6,800 feet in elevation, traverse the grassy and rocky southeast slope of Saint Paul Peak until you reach the obvious west ridge of Rock Peak at approximately 2 miles from the trailhead (6,590 feet).
From the start of the ridge. Proceed eastward along the crest through large slabs, which make the initial climbing pleasant. In spots of thick trees, traverse to the south side of the ridge on goat trails. The route is easy class 3 if you look hard but expect to get into some class 4 or even a few low 5 moves. The upper section is steep and ends with a short romp through talus to the summit where you'll find a register left by "Yukon Jack."
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