Red Box Trailhead to Valley Forge Campground

From the trailhead located along Hwy 2, look for the sign at the top of some stone steps. Head down and the dry grassy route will quickly enter the trees and descend along the west fork of the San Gabriel River. The riverbed is dry most of the year so bring plenty of water. After about a mile, look for a marker as you cross Rincon Red Box Road to pick up the trail on the other side. Off to the right of the trail you'll spot some big buildings. This is the site of the Long Beach School District's Hi-Hill Outdoor School. It has been closed since 2008 due to fire danger and cost savings but was spared by the Station Fire in 2009. You'll pass several old cabins soon after but another marker below them marks the continuation of the Gabrielino Trail (NRT). The trail cuts through a big patch of blackberry bushes. Take a few to power you through the next section of trail if the season is right.About 1.5 miles past the road you'll see a sign to Valley Forge campground and leave the Gabrielino Trail (NRT) to the left. Continue along a short downhill stretch and you'll arrive at the campground. There are several picnic tables, some signboards and vault toilets at the campground. The journey back out to the Red Box trailhead will take a little longer as you climb back up the arroyo.A popular variation that uses a short car shuttle is to take the Valley Forge Trail #12W09 down from the Mt. Wilson Red Box Road and return back to Red Box on the Gabrielino Trail (NRT).

The Long Beach School District's Hi-Hill Outdoor School (closed since 2008) is midway along this route.