Thorofare Trail

The Thorofare Trail is a 33.1-mile one-way route from Nine Mile Trailhead on Yellowstone Lake’s east shore into the remote southern Thorofare. It is a multi-day backpack, not a day hike. There’s no road pickup at the far end, so plan a permitted route that continues through the southern trail network or be ready to hike back; an out-and-back is roughly 66 miles. The park rates the trail moderate, but its length, repeated fords, and isolation make this a hard commitment.

The first couple of miles pass through forest burned in 2003 and 2011. Yellowstone Lake first comes into view around mile 3.4; after Park Point and Meadow Creek, the path stays close to shore for nearly two miles. Look across the southeast arm toward the Promontory and the pale outcrop at Brimstone Basin.

Around mile 15, Terrace Point has benches left by higher lake levels. The shoreline still shifts as movement beneath Yellowstone Lake tilts its basin, so this stretch gives you a good look at both the lake’s older edges and its changing southern arms. Farther on, views open over the Yellowstone River delta toward Colter Peak.

The route reaches the Yellowstone River around mile 20, then continues through meadows, forest, and additional creeks. Trappers Creek comes near mile 23.5, and a junction near Mountain Creek leads toward Eagle Pass. The line keeps going through the remote Thorofare rather than ending at the first river view.

The two-room Thorofare Patrol Cabin was built in 1915 by the U.S. Army for backcountry patrols and is still used as a park base. It sits near the remote end of the route, not at a road-accessible pickup. Published maps place the cabin and the southern trail end at slightly different mileages; use 33.1 miles as a planning figure and confirm the exact endpoint and campsites on your backcountry map.

Several creek and river crossings require fords. The water can be swift and cold, and snowmelt can make crossings more difficult. The trail passes through or near three bear management areas, where additional access rules may apply; check current restrictions before setting out. An overnight trip requires a backcountry permit and designated campsites. Pets are not allowed on park trails or in the backcountry.

Allow about 16 hours of hiking for the one-way line, usually split across two hiking days; that estimate excludes camp time, delays, and any return route. Start at Nine Mile Trailhead (5K5) on Yellowstone Lake’s east side. Its listing identifies a trailhead and information kiosk but gives no parking capacity, toilet, or potable-water details. The remote Thorofare Trailhead (6K2) is not road-accessible.