Pets allowed
Elevation Gain
5,184.00 ft (1,580.08 m)
Trail type
19.10 mi (30.74 km)
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Lake Ave to Red Box is a challenging, 19.1-mile out-and-back in Angeles National Forest, near the city of Altadena. The route connects the foothills of Altadena to the San Gabriel Mountains, with options to summit four peaks in the area. It is popular with trail runners and hearty hikers, and packs a lot of elevation into each mile.

Park in the residential neighborhood off Lake Avenue or Loma Alta Drive, and pass through the gates of the Cobb Estate, a Forest Service nature preserve with a rich Altadena history. There is usually water at the trailhead water fountain here, which you won’t find again until the Red Box parking area over 9 miles and a few mountains away.

Take the Lower Sam Merrill Trail, which will start you out on a 2.7-mile, manageable climb to Echo Mountain. Note that this lower portion of the route can get very crowded. Check out some of the interpretive signs and historical remains at Echo Mountain regarding Mt. Lowe Railway and the former Inn here. From Echo Mountain, take the Middle Sam Merrill Trail. Continue to climb another 2.5 miles, and after a relatively flat, oak-shaded segment, you’ll pop out onto the dirt Mt. Lowe Motorway. Go straight for a short distance here, until you turn right onto the East Mt. Lowe Trail. This will take you along the shoulder of Mt. Lowe, where you’ll have the option to summit the peak, with another summit option of Mt. Markham shortly after.

The Mt. Lowe Trail will take you to Markham Saddle at mile 8 of the route. Take the left trail toward San Gabriel Peak, where, at the top of the climb, summits of San Gabriel and Mt. Disappointment are accessible. This trail will lead to a short section of road before the Bill Riley Trail, downhill and to the right. Come out onto the Mt. Wilson Road and take the shoulder down a short distance to the Red Box parking area. This marks the halfway point of our route. Be sure to stop in the Haramokngna American Indian Cultural Center, which features exhibits of the tribes of the San Gabriel Mountains, and sells snacks and drinks. There is also drinking water located just outside the Cultural Center. Turn around and head back the way you came, or take any of the numerous variations on the way back to Cobb Estate.

Logistics + Planning

Preferable season(s)




Parking Pass


Open Year-round



Wildlife. Scenic vistas. Close to other adventures. Historical significance.


Crowded in certain sections. Very exposed to inclement weather.

Trailhead Elevation

1,743.00 ft (531.27 m)

Highest point

5,774.00 ft (1,759.92 m)


Historically significant
Family friendly
Big vistas
Potable water
Native artifacts
Bird watching

Typically multi-day


Permit required



Nearby Lodging + Camping


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