1.9 mi from the trailheadHeadwaters Campground at Flagg Ranch
Campground · Wyoming

16.3 mi out & back · 2,057 ft gain · 7,726 ft high point · Very hard
From South Boundary West Trailhead
In Yellowstone National Park · Wyoming · National Park Service
South Boundary Trail from South Boundary West Trailhead reaches Grassy Lake Reservoir for 16.3 miles out and back in Yellowstone, climbing 2,057 feet.
2,057 ft of gain round trip.
The closest places to sleep, measured from the trailhead.
Ranked the same way, within twenty-five miles.
What the trail reaches, measured from the start.
The route at the trailhead. Drag with two fingers, or hold a key to zoom.
Trail data: USFS, NPS, © OpenStreetMap contributors (ODbL). Elevation: USGS 3DEP via Mapzen terrain tiles. Nearby reading: Wikipedia. Photos: Wikimedia Commons contributors, licensed as shown on each photo. Download the trail and feature data.
Campground · Wyoming
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Sun: Chance Snow Showers then Rain Showers · wind 5 mph ESE