

San Dimas Canyon Loop
- Location: Horsethief Canyon Park, San Dimas. From points east, take the 210 Freeway to the Foothill exit. Turn right on Foothill Blvd. and go 0.4 miles to San Dimas Canyon Road. Turn right and go 0.3 miles and bear left on Sycamore Canyon Road. Go 0.2 miles and turn left onto Horsethief Canyon Road and follow it to the parking area. From the west, take the 210 Freeway take the San Dimas Avenue exit. Turn left and go 0.4 miles to Foothill Blvd. Turn right and go 0.8 miles to San Dimas Canyon Road. Turn left and follow San Dimas Canyon Rd. for 0.3 miles and bear left on Sycamore Canyon Road. Go 0.2 miles, turn left on Horsethief Canyon Road and follow it to the parking area.
- Agency: L.A. County Parks & Recreation; City of San Dimas
- Distance: 2.2 miles
- Elevation gain: 550 feet
- Difficulty Rating: PG
- Suggested time: 1.5 hours
- Best season: Year round (hot during the summer)
- USGS topo map: Glendora
- Recommended gear: sun hat
; hiking poles
- More information: Trip description (hiking clockwise with the steep climb first) here; San Dimas Canyon Park page here; Horsethief Canyon Park Yelp page here
- Rating: 6

This loop, which visits L.A. County’s San Dimas Canyon Park and the City of San Dimas’s Horsethief Canyon Park, offers a pleasant variety of scenery and a surprisingly good workout, conveniently located to the residential neighborhoods of the San Gabriel Valley and western end of the Inland Empire. Hikers who think they’ve seen it all when it comes to this area might want to give this loop a look.

From Horsethief Canyon Park, follow the main fire road past a gazebo, playing field and dirt horse track. The trail bends to the right and reaches a Y-fork. Take the left path, following it past a lone willow tree to an intersection a quarter mile from the start; this is the beginning of the loop. The straight route is your return. Take a hairpin right turn and follow the trail through a pleasant grove of oaks, dropping into San Dimas Canyon near a group of stables (0.5 miles.)

Here, take a hard left and follow the trail gradually uphill, passing by more oaks, paralleling Sycamore Canyon Road. Don’t be deterred by a yellow “Trail Closed” sign; according to local hikers and equestrians who frequent the area, this warning exists simply for liability purposes as you are now on land not under the jurisdiction of either park. As of this writing the trail appears to be fairly well maintained and regularly traveled.
At 0.9 miles, you reach an attractive clearing where you can rest at a picnic table; an abandoned stone chimney pokes up from the grass. From here, pick up the Poison Oak Trail (don’t worry, there are only trace amounts of the hated plant) which heads uphill through a narrow, wooded tributary of San Dimas Canyon, reaching a fire road at 1.2 miles.

From here, turn left and follow the road uphill, enjoying a nice view of Mt. Wilson and the western San Gabriels through the trees. At 1.5 miles, you reach a clearing with picnic tables and outstanding vistas including the Ontario/Cucamonga Ridge, San Gorgonio, San Jacinto, the Santa Anas, downtown Los Angeles and a nearly aerial view of the neighborhoods below.

After enjoying the panorama, look for a steep trail descending past a pair of white posts. Loose in some spots, the trail switchbacks expeditiously back down to the junction, completing the loop. From here, retrace your steps back to the parking lot at Horsethief Canyon Park.

Text and photography copyright 2015 by David W. Lockeretz, all rights reserved. Information and opinions provided are kept current to the best of the author’s ability. All readers hike at their own risk, and should be aware of the possible dangers of hiking, walking and other outdoor activities. By reading this, you agree not to hold the author or publisher of the content on this web site responsible for any injuries or inconveniences that may result from hiking on this trail. Check the informational links provided for up to date trail condition information.
