

Sierra Peak
- Location: Corona. From the south, take I-15 to El Cerrito. Turn left and go a total of 4.4 miles on El Cerrito, which becomes Foothill Parkway. At Trudy Drive, make a U-turn and park on Foothill Parkway facing east in one of the few spots designated for the Skyline Trail. From the 91 Freeway, take the Lincoln Exit and head south (left if you’re coming from the west, right if from Riverside) and go 2.6 miles to Foothill Parkway. Turn right and go 0.7 miles to the intersection with Trudy Drive, make a U-turn and park where available facing east on Foothill Parkway.
- Agency: Cleveland National Forest, Trabuco Ranger District
- Distance: 15 miles
- Elevation gain: 3,000 feet
- Suggested time: 7 hours
- Difficulty rating: R (Distance, elevation gain)
- Best season: November – March
- USGS topo maps: Black Star Canyon, Corona South
- Recommended gear: Sunblock
; Sun Hat
; Insect Repellent
- Recommended guidebook: Afoot and Afield: Orange County
- More information: Trip description here; Everytrail report here
- Rating: 9

Sierra Peak (elevation 3,045) is the northernmost major summit of the Santa Ana Mountains. On clear days, the views both on the ascent and at the summit are outstanding. Though it requires significant endurance to reach the summit, the terrain and navigation couldn’t be easier, making this a good training hike.
From the parking area, follow the paved Skyline Drive trail south then west around the back of a residential neighborhood. While this first part of the hike is less than truly inspiring, once you leave the houses behind at half a mile, passing by a metal gate into Cleveland National Forest land, the terrain becomes more scenic as you make your way up Tin Mine Canyon.

At just over a mile, Skyline Drive makes a sharp right turn and begins its ascent. For the next 3.3 miles, it winds along the side of a ridge, alternately providing nice views of the Inland Empire and all three major ranges (San Gabriels, San Bernardinos and San Jacintos) and of the Santa Anas themselves. As you make your way higher, you’ll see the ridgeline of Main Divide Road.

At 4.3 miles, the trail dips down to a saddle before climbing back to reach a junction called Oak Flat, with several communications towers (5 miles.) Head right on Main Divide Road, threading your way between two parcels of private land. For the next 2.5 miles, the trail continues to follow a ridge. Although Sierra Peak is only 350 feet higher than Oak Flat, several significant ups and downs along the way add up to over 1,000 feet of total elevation gain coming and going.

The great views to the east continue, and if you’re lucky you may get a glimpse of Catalina Island. You’ll also likely notice Sierra Peak’s antenna-covered summit ahead of you to the north. At 6.6 miles, stay straight as another fire road branches off to the left. You make a significant drop to a saddle and then one final climb to a short spur leading to the summit.

As on Santiago Peak, the antennas block the view, but it’s still possible to find places to sit and enjoy the panorama. You get a nearly aerial perspective on the Chino Hills and north Orange County, with the 91 Freeway slipping by below. After resting your legs return via the same route.

Text and photography copyright 2013 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.
