One of many excellent hikes/runs in the Southern Sierra, the River Trail starts at Johnsondale Bridge — about 19 miles north of Kernville, California on highway Mountain 99 — and follows the river north 4 miles to Four Mile rapid. Here the trail turns east and works up to the Rincon Trail.

This section of the Kern River is part of the beautiful and challenging Forks of the Kern class V whitewater run. Numerous class IV rapids and the class V rapids Carson Falls and Confusion are found on this reach. In the Spring and Summer expert kayakers and rafters may be seen maneuvering among the many boulders and drops. (A Forest Service permit is required to paddle the Forks.)