South Fork Trinity River Trail

South Fork Trinity River Trail (#8E18) is a long, river-following hike in the Shasta-Trinity National Forest. It traces the South Fork Trinity River through rugged, lightly populated country, with the typical character being old narrow-gauge wagon-road heritage and generally gentle grades on much of the route.

Use patterns for this trail are typically day-to-day hiking or short backpacking with primitive camping along the corridor. Water is described as generally plentiful along the route, but conditions vary and some crossings are unbridged, so plan around wet feet and limited “escape” options once you’re committed to a stretch upstream.

A widely used section runs upstream from the Scotts Flat area toward the mouth of Smokey Creek. Within that stretch you’ll encounter multiple small creek crossings (some bridged, some not) and a suspension footbridge at Scotts Flat Campground (noting the bridge status described for this trail can change).

For longer mileage, continuing farther up-river on the same overall alignment takes you toward Double Cabins on FS 29N30. The route is managed as a National Recreation Trail, and it’s explicitly listed for hikers and equestrians, with mountain biking allowed on some stretches.

The trail is used year-round by hikers, but winter and early spring can bring snow in the upper sections and along nearby access corridors. Trail use is remote, with no amenities along the route, so carry everything you’ll need and plan for long stretches between reliable resupply points.

Trail maintenance is described as infrequent (often only once per year), so expect occasional downed logs and less-defined path conditions—especially as you push upstream into the less-used parts of the corridor.

More information: Visitor information, Visitor information, South Fork: Up River