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South Fork of the Santa Ana River via Dollar Lake



19.7 mile 31.8 kilometer out and back
81% Runnable


Ascent: 4,569' 1,393 m
Descent: -4,568' -1,392 m
High: 11,440' 3,487 m
Low: 6,915' 2,108 m


Avg Grade: 9% (5°)
Max Grade: 71% (35°)


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Trail shared by Ben Crowell

Run a moderately graded route to the highest point in Southern California.

Ben Crowell

Features River/Creek · Views · Wildflowers · Wildlife


This is the second-shortest route to the summit of San Gorgonio Mountain, the shortest being the much more crowded Vivian Creek route. The main disadvantage is that no water is available from mile 4 to mile 15 of an out-and-back. The lower elevations are not as scenic as they used to be, due to a fire that burned a lot of the trees, but there are still wildflowers, meadows, and ferns. The higher elevations, in the alpine zone, are very beautiful, and this trail affords views of both the Santa Ana River and Mill Creek watersheds.

Need to Know

A National Forest Adventure Pass is required in order to park at the trailhead, where there are bathrooms. Water is available at the trailhead by scrambling down from the parking lot to Frog Creek. Wilderness permits are no longer required for day use, but are recommended. They can be obtained from a box outside the Mill Creek Ranger Station and pushed through a slot. The nearest food, gas, and lodging are in Angelus Oaks. The Oaks Cafe in Angelus Oaks closes at 2 p.m. on Monday through Thursday. This is a committing run in a remote, high-elevation backcountry area. On a weekday, it will be common not to see any other people on this trail, so self-reliance is required. Before attempting this run, it would be wise to first try running to the summit from Vivian Creek, which is a shorter route, has more water sources, and is more heavily traveled. Because of winter snow and cold temperatures, this is best as a summer excursion to escape the heat in the city.

Runner Notes

Compared to Vivian, South Fork is more moderately graded, so there is a greater percentage of the trail on which a typical running will actually be able to maintain a running gait.


Head up the well-marked trail from the parking lot at the South Fork Trailhead on Jenks Lake Road. Four miles in, the trail reaches South Fork Meadows and sidles up next to the South Fork of the Santa Ana River. This is the last reliable year-round water source on the route.

From South Fork Meadows, take the right-hand fork of the trail, heading up a ridge past Dollar Lake. This section has most of the steepest climbing. Continue past the spur trail for Dollar Lake to Dollar Lake Saddle. There is a four-way junction at the saddle with a metal sign.

Turn left and take the southeast trail toward the summit of San Gorgonio. The slope becomes more moderate again. The trail now leads around the south sides of Charlton and Jepson peaks. At the saddle between these two peaks (mile 7.2) is a confusing spot where the trail takes a sudden 90-degree turn around a lean-to built out of logs and branches. Carefully note this spot, which is more confusing on the way back. The trail now enters the alpine zone.

At mile 9 is a signed junction with the Vivian Creek Trail. Carefully note this junction, which is less obvious on the way down. Continue east toward the summit. A second sign, at mile 10, marks the Sky High Trail, which you don't want. Stay left for the spur leading to the summit. Continue past a false summit to the true summit block of San Gorgonio Mountain, which has a wooden sign and a trail register.

Return by the same route.

The relevant USGS 1:24,000 maps are Moonridge and San Gorgonio Mountain.

Flora & Fauna

Deer, squirrels, chipmunks.

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Approaching the summit of San Gorgonio Mountain, a.k.a. "Old Greyback"
Aug 24, 2016 near Big Bea…, CA


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