Rocky Mountain National Park: Chasm Lake
For the ultimate view of Longs Peak's 1,000-foot Diamond Face, climb to Chasm Lake on this 8.2-mile out-and-back that tops out above treeline.
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From the Longs Peak Trailhead, follow a wide path that climbs steadily through ponderosa pine. This trailhead is more remote than others in the national park, but as the gateway to the park’s only fourteener, it can be a veritable highway of hikers in July and August.
Switchback upward, occasionally edging mountain streams, until you reach treeline just past mile two. From here, the trail heads across a wide, rocky basin toward Longs Peak, which is now in view. Crest a small ridge at mile 3.2—this is a great place to drop your pack for a quick snack, photo op, and use the privy, if necessary. (Why not? It has no roof and a great view of Longs’ 1,000-foot Diamond Face.)
From here, edge left down into the valley that leads up to the Diamond. In early to mid summer, cross a patch of snow on the descent to columbine-lined stream crossings in front of a patrol cabin.
South of the cabin, scout out cairns on the rock above marking the path. In five or ten minutes, summit the class II scramble to impressive views of the Diamond and icy Chasm Lake at its base. Shoo away aggressive marmots and chipmunks as you search for climbers on the Diamond and Ship’s Prow, to the left.
Permit Required for entrance to park Contact Rocky Mountain National Park
-Mapped and photographed by Jenn Fields and Chris Hood