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Sunset Ridge / El Prieto Loop from Millard Campground

 13 votes

14.3 Miles 23.1 Kilometers



2,961' 903 m


-2,987' -911 m


3,428' 1,045 m


1,316' 401 m



Avg Grade (4°)


Max Grade (13°)

Minor Issues

25 days agoUpdate

This is a good, tough loop which includes steep climbs rewarded by great singletrack descents.

David Gregg


Both Sunset Ridge Trail and El Prieto Trail rest on north-facing slopes, so enjoy large amounts of shade. This means lots of trees, cooler temps, moist soil, and beautiful green everywhere. These trails are gems of the San Gabriel Mountains and I highly recommend them, but bring your big-boy attitude to this ride.

Sunset Ridge Trail is a technical, fairly steep, singletrack. The trail never gets more than two feet wide at any point except some switchbacks. There are one-foot boulder-pile drops in the middle of cliff exposure; sometimes two right on top of each other; sometimes in the turns. There are switchbacks so tight that I had to wiggle around them on my toes... on cliffs. There's a staircase down TO a switchback at some point. In the space between features, there is steep, there is narrow, and I felt most of the time to be on the edge of danger. It's quite a thrilling drop.

The El Prieto Trail has many 2'-6' deep creek crossings during the winter. Though lacking the amount of cliff-side real estate of Sunset, this trail has a ton of technical moments. There are rock gardens, drops into crossings, tight switchbacks, cliff-face ribbons of trail, log drops. I think, overall, that El Prieto, though shorter, is the most satisfying of the two. It has more variety, and the terrain is somehow more soothing.

Poison oak is common on both of these single tracks. Sunset Ridge Trail and El Prieto Trail are also popular hiking and running trails so please use a bell and be courteous of other trail users.
Dogs: Leashed

Need to Know

You'll need a $5 National Forest daily adventure pass to display in your window, most local bike shops and big sports stores will have them.

Alternatively, if you are up for an even more challenging ride, park for free at Loma Alta Park (…) and climb up the Horse Trail. This is a steep, technical ascent but strong riders will only dismount a few times. The trail intersects with the Chaney Trail road midway, so you can skip the steepest section and climb the paved road to the campground.


Park at the top of Chaney Trail (flashing yellow light on Loma Alta Dr.), a steep residential street that turns into a twisting National Forest road (if full, turn left at the top and go downhill to the Millard Campground lot. Ride bike back to top of Chaney). Go around the swinging gate, and right away the paved fire road, Mt Lowe Rd, gets steep and weaves a few times. It levels off for a hundred yards and on the right will be a fenced-in forest service facility.

At the end of this facility, look left and take notice of the trail that drops to Millard Campground, you'll be going that way later. For the next two miles, the builders somehow found a way to weave this paved fire road up a mountain without deviating from a 12% incline for a single inch. I mean... STEEP. So put your head down, find a rhythm, and try to ignore the pain. There will be a left-hand split half-way up, but stay right.

At exactly 2.3 miles from the gate, look for a trailhead on the left with a sign post. I remember a couple of trees standing near the trail entrance. See the overview above for details on Sunset Ridge Trail.

2.4 miles down from the top, Sunset Ridge Trail eventually merges from the right, like a freeway, onto the pavement of Mt Lowe Rd near the forest service facility. Remember that trail I told you to notice? Now take that right-hand drop to Millard Campground and enjoy, finally, the ability to open it up a little on the flowy section. At the trails end, say hi to the campers as your passing kicks a few leaves into their sites. The path turns into dirt fire road and a one-mile climb starts, up 300 feet, along Millard Canyon Rd.

The road peaks then starts to descend. Take the first right-hand turn on a fire road after 1/4th mile of downhill (if you end up at a gate with a house on the left, you missed the turn). This short section leads to the entrance of El Prieto Trail, but from its south side instead of the north like most everyone else does. Look for a small, left-hand drop into the forest below, with an old tire wrapped around the base of the trail sign.

El Prieto Trail has a few trail splits to the right. You'll always be safe staying left, but I have taken the third right and it's a fun alternative, merging at the picnic tables a short distance away. For more details, see the overview above.

1.7 miles from the top of El Prieto Trail, it ends at the start of Brown Mountain. Stay right and begin a fairly substantial climb of 1100 feet over 2.6 miles to Brown Saddle Junction, a plateau beneath a tight group of tall pines. Don't take the uphill left, that's another trail. Stay straight through the plateau and begin a one-mile descent on Fern Truck Trail back to the entrance of El Prieto Trail. Backtrack east along Millard Canyon Rd, and for your last challenge of the day, climb the steep paved road from the campground parking lot to your car at the top of Chaney.

Hope you enjoy this route as much as I did. I know it's a pain to get a pass to park, but it feels so remote and forest-y up there, like you're miles and miles from the city, even though you're not. It's really a cool place to go for the day, or for a weekend biking/camping trip to explore that whole region.


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4.5 from 13 votes

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Sep 19, 2017
Jon Dunbarr
Sep 13, 2017
Jon Dunbarr
Sep 9, 2017
Dan Hill
May 20, 2017
Dec 4, 2016
Charly Baker
downhill was awesome. climbing wasn't bad except the brown mountain climb at the end. would be cool to find a better way back to Trailhead from bot... 13.2mi
Jun 25, 2016
Erik Guevara
Jan 2, 2016
Rick Barbee
Rode from street parking near JPL up to Sunset Ridge, down Sunset Ridge to El Prieto....amazing downhill....nice exposure and tight switchbacks! 18mi — 2h 30m
Dec 27, 2015
Jeff Gray
started from JPL parking lot 15.5mi — 3h 30m

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  4.5 from 13 votes


in Arroyo Seco


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Minor Issues 25 days ago
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Directions for the splits on El Prieto are iffy. If you always stay to the right, you will follow the original trail and enjoy a few extra switchbacks. The first two lefts rejoin & are easier options. The next two lefts will take you out of the canyon, first up to the connector between Brown Mtn Rd and The Meadows (near Owen Brown's gravesite), and the second directly into The Meadows. May 3, 2017

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