Carbon Canyon Road (SR-142) Cycling Guide

Overview

Carbon Canyon Road links north Orange County with Chino Hills through a narrow, wooded canyon. It is the go-to climb for riders in Brea, Fullerton, Yorba Linda and Placentia, and it feels surprisingly rural for a road this close to the suburbs. The climb is moderate, the scenery is green after winter rains, and the descent is fun. It is also a state highway with commuters, so the timing matters.

Because it is close to so many North County neighborhoods, it is easy to ride from home and back without driving.

The route in plain words

Start near Carbon Canyon Regional Park in Brea and head east on Carbon Canyon Road (SR-142). The road climbs steadily through the canyon past the small community of Sleepy Hollow, crosses the county line into San Bernardino County, and tops out before dropping to Chino Hills Parkway. Many riders turn at the summit and descend back to Brea; others continue into Chino Hills and loop back via Grand Avenue or other routes. Several Bikeclimbs segments cover the climb from Valencia Avenue or from the park to the top.

Returning toward Brea, the descent is fast and fun but has some tight curves; scrub speed before the corners rather than in them.

Distance and elevation

TougeMap measures the road at about 8.4 miles from Brea to Chino Hills Parkway, rising from about 466 ft to about 1,152 ft, with a total vertical change of about 1,329 ft in both directions and a steepest sampled grade of 6.3%. The climb from the Brea side is moderate rather than steep. Distance from your door will vary.

Best time to ride

Ride it early on weekend mornings. Weekday rush hours are busy with commuters cutting between the 57 and the 71. After heavy rain, check for closures: the canyon has had slides and flooding. Summer afternoons are hot.

Water and coffee stops

There are few services in the canyon. Carbon Canyon Regional Park at the bottom is the natural meeting point and has park facilities; check that fountains are on before relying on them. Shopping centers in Brea and Chino Hills at either end are the reliable places for coffee and food.

Safety notes

The road is narrow with limited shoulders in places, sharp bends, and impatient traffic at commute times. Ride single file, use lights, and choose the weekend early-morning window. Descend predictably and watch for gravel on the inside of curves. Do not stop in blind bends.

Which bike and setup

Any road bike with standard compact gearing handles Carbon Canyon. A 28 mm tire is enough; 30 mm adds comfort. Because of traffic, a bright rear light with a daytime flash is essential.

Before you go

North County riders, we are a short drive away. If your shifting skips on the climb, our tune-up or electronic shifting service will sort it. Call (714) 760-4908.

Quick facts

County: Orange County
Start: Carbon Canyon Regional Park area, Valencia Ave / Carbon Canyon Rd, Brea
Distance: About 8.4 miles from Brea to Chino Hills Parkway
Climbing: About 1,300 ft total vertical change (road rises from about 466 ft to about 1,152 ft; steepest sampled grade about 6.3%)
Surface: Paved state highway
Difficulty: Moderate climb; traffic at commute times

Pair it with

Carbon Canyon pairs naturally with a spin on the inland end of the Santa Ana River Trail. If you want a much bigger climb in the same part of the world, Glendora Mountain Road is about half an hour north.

Frequently asked questions

How long is Carbon Canyon Road?

About 8.4 miles from Brea to Chino Hills Parkway, according to TougeMap's measurement of SR-142.

How steep is Carbon Canyon?

Moderate. The road rises from about 466 ft to about 1,152 ft, with a steepest sampled grade around 6.3%.

Sources

Distances and climbing are from the published sources listed above and are approximate; roads, closures and conditions change. Check current conditions before you ride.

More Orange County ride guides

All guides: Southern California ride guides. Veloaded Cyclery has one location, at 3420 W MacArthur Blvd Suite B, Santa Ana, CA 92704: service menu, bike fitting.