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Bend, OR: South Sister via Obsidian Trail

Link pumice and obsidian fields with expansive alpine meadows on this challenging trek to the top of South Sister, a glacier-capped volcano in the Cascade Range.

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Twenty miles west of Bend, the rugged, glacier-covered slopes of South Sister rise dramatically above Deschutes National Forest. The tallest of a trio of volcanoes known as the Three Sisters (and Oregon’s third tallest peak), South Sister’s summit reveals dramatic views across the Cascade Range.
Start this challenging trek at Frog Campground and head southeast on the Obsidian Trail. You’ll gain roughly 5,500 feet of elevation and travel from forested landscapes to stark slopes covered with volcanic pumice and obsidian. After 20 miles, rest by a small lake on South Sister’s false summit before the final, 1-mile push to the summit (which gains almost 2,000 feet of elevation). Savor the sky-high views from the crater rim—Middle Sister, North Sister (and Mount Hood, on very clear days) can be seen to the north—then follow the same route back to the trailhead.
-Mapped by Trung Q. Le

To Trailhead

US 97 N to US 20 W to Sisters, OR. Turn left onto S. Hood St. In 0.2 mile, right onto OR 242/McKenzie Hwy. In 21 miles, left onto NF 1624. In 0.2 mile, left at fork. Go 0.2 mile to parking. Follow signs for Frog Camp and Obsidian Trailhead. Note: McKenzie Hwy. and NF 1624 are closed seasonally.

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