Distance (round-trip)

10.3 mi

Time

7 hrs

Elevation Gain

3950 ft

Season

Spring
Summer
Fall

Weather

A leg-busting ascent to the highest point in Los Angeles County, with a neighboring mountain thrown in for good measure. This is a classic hike through some incredible subalpine scenery, and is a MUST HIKE for anyone who lives in or is visiting Southern California, provided you’re up to the challenge — and please, don’t underestimate this trail just because it’s close to cities.

The Mount San Antonio (or, Mount Baldy, if you’re feeling colloquial) trail is hands-down one of the best in Southern California. It’s the highest peak in the San Gabriel Mountains at 10,069 feet (or 10,064, depending on who you ask), and its tree-free summit provides incredible panoramic views of almost every single kind of SoCal terrain — from desert to city to mountains to ocean. There are two popular routes to the top – and they’ll both make you work for it. But once you get there and collapse high above the rest of civilization, it’s absolutely worth it.

However, please note that while Mount Baldy can be done as a tough but not-especially-technical day hike, it is a Serious Mountain. Because this mountain has a steep face and sits on the border between the Mediterranean and desert climates in Southern California, this region has a tendency to make its own weather without much notice. Crushing thunderstorms have been known to appear in the summer and fall, and during the winter months this trail is likely to be covered in ice and snow and require real technical know-how. People can and do die on this trail, so please take it seriously.

The fire road leaving Manker Flats had very recently been repaved — so the first three-quarters of a mile were on fresh asphalt. Your feet may not be happy, but the views of the Baldy Bowl and the distant summit are more than enough to take your mind off the urban footing.

At that 0.5 mile mark, there’s a small spur trail that leads to the bottom of San Antonio Falls. If you can get there on the first few warm days of spring, you can get absolutely drenched by the 80 foot waterfall. Assuming, of course, we’ve had some snowfall over the winter. Even with our record-breaking bone dry winter of last year, though, the falls still had a bit of water left in ’em.

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The fire road becomes unpaved at this point and continues on a long and winding path up to Baldy Notch. It’s a pleasant, easy walk with plenty of views of the San Antonio valley, but compared to what comes later on in the trail, it’s a bit boring.

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In fact, if you choose to do so, you can skip parking at Manker Flats and instead pay a few bucks to park at the Mount Baldy Ski Lift, which will cart you up to Baldy Notch in just a few minutes and cut about 1300 feet of elevation gain and just under 3 miles off your legs. But it’s cheating. There, I said it.

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When you get to Baldy Notch at 3.3 miles, you can stop in the ski shack and grab a snack, take a break, and warm up if it’s chilly. When you’re ready to keep moving, head northwest toward another ski lift.

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Here, the trail gets a little tricky to follow. The “proper” route follows an unclear fire road to the left of the ski lift towers, which will take a few short switchbacks to climb to a ridge overlooking the Antelope Valley. I forgot this, and instead followed a snow fence that ascended right up a ski slope. If you think it’s fun going down a ski slope, I can assure you it most definitely is not fun to hike up one. It is, however, a short and direct route with some pretty impressive views of the San Bernardino Mountains to the east.

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Generally if you head in a north-northwesterly direction, you’ll find the Backbone trail with no problems. It’s only right near the lodge that the trails and roads are unclear. Soon, you’ll reach a ridge that has a noticeably steep drop-off to the north. You’ll be looking across a deep, flat wash valley to the gray beast of Dawson Peak.

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And directly to your west is the start of the Devil’s Backbone — one of the most exciting (and potentially dangerous) trails in the San Gabriels.

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The first section of the Backbone literally straddles an east-west ridge between two steep valleys. It’s wide-enough at the start, but if you catch yourself looking down at the wrong time, it’s pretty easy to get a touch of the vertigo. This is a section of trail to treat with respect and take seriously. There’s a stretch after the first section that hugs a fairly steep cliffside where the trail thins considerably. It can be a little nerve-wracking for those with a fear of heights, but just take your time and stay calm. You’ll likely have more room than you thought you’d have, and soon you’ll be back on wider terrain.

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When the trail straightens out and heads directly toward the Baldy Bowl, you’ll see a steep, bare peak directly to your north. This is Mount Harwood. I took a cross-country talus scramble up to the top, just because it’s on the Hundred Peaks List and I hadn’t bagged it yet. It’ll give you a decent view of the approach of San Antonio, and is much less-visited than it’s bigger neighbor but it’s still worth a visit. Just mind your footing on the loose scree. This picture is from the summit, looking down at a fellow hiker who I’d just passed. It gives a nice scale to the scope of the surrounding landscape.

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From there, it’s a short, steep, slippery scramble back down to the Backbone Trail. Then it’s down into a windy saddle and a long, slow crawl up to the Baldy Summit.

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No matter which way you try to bag Baldy, it always seems like the last mile or so is the toughest part. You’re slogging up a barren, windswept landscape along trails that either relentlessly switchback, or shoot no-nonsense directly to the summit. From this route, the last mile has just over 500 feet of elevation gain — but because you’re up so high, and you’ve already climbed so much, it feels like twice that amount.

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But for all the work you put into this hike, when you finally reach the summit, the sense of accomplishment is unreal. There are small makeshift wind shelters left behind by previous hikers, and all you’ll want to do is lean up against one of them, take a deep breath, and soak in the unparalleled 360-degree views of the wilderness around you.

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When you’re done taking in the views and / or recuperating from the climb, you can either head back to the Devil’s Backbone the way you came (and probably take the ski-lift down — no shame in descending), or you can take in some more of what Baldy has to offer by heading south from the summit onto the Baldy Bowl Trail. If you feel like you’re heading west along the ridge for too long, you’re probably on the Baldy Trail — a much longer route that will take you to Mount Baldy Village — far away from where you probably parked.

The correct route is a single-track that takes you just outside the western edge of the Baldy Bowl, as the landscape goes from windswept-lunar to slightly-less-windswept, populated with some interesting, twisted pines.

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It’s worth it to go off trail once or twice for a dizzying view off the cliff of the Baldy Bowl. Otherwise, the trail will eventually switchback its way past an incredible torn tree, and deposit you directly in the center of the Baldy Bowl, among the hundreds of boulders that have slid down over the years.

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It’s another great place just to stand and marvel at the sheer size of the land — and know that you were just walking along that ridge 2000 feet above where you’re feet are now.

From there, the trail follows the contour of the Bowl past the Sierra Club San Antonio Ski Hut (where you can stay overnight for a small fee if you’re interested), and gradually makes its way back down to the Mount Baldy Fire Road, just east of San Antonio Falls.

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And from there, it’s just a short walk back to Manker Flats, where you’ll most likely give yourself a pat on the back, take off your shoes, and head for the nearest source of cooked food you can find. (I dig the Mount Baldy Lodge on the way out).

And congratulations. You just hiked the highest mountain in Los Angeles County.

Founder and Editor-in-Chief of Modern Hiker, Author of "Day Hiking Los Angeles," Walking Meditator, Native Plant Enthusiast.





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238 Comments

John Flores Feb 26, 2019 19:02In reply to: Casey Schreiner

Thanks so much for the reply!! I just moved to LA and went to your blog for hiking ideas! I will definitely wait till the summer then instead.

I was going to do Baden-Powell hike but I think there is snow too from what I was reading...

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Casey Schreiner Feb 23, 2019 08:02In reply to: John Flores

John,

Take the route I describe here and reverse it - you can head up via the Ski Hut Trail and then just do an out-and-back instead of a loop. This trail is shorter but significantly steeper than the route that takes you across the Backbone.

Also note that in the winter, this is a TECHNICAL WINTER HIKE. You'll need crampons, ice-axes, a helmet, and the know-how to use them. If you're just looking for a tough and rewarding day hike, I'd wait until the summer when the snow melts off.

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John Flores Feb 22, 2019 17:02

Can I get to the summit without going through the Devil's Backbone? I am kind of terrified of heights but would love to go to the top without having to walk through the backbone...

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Casey Schreiner Apr 23, 2018 08:04In reply to: Chris May

Like anything, the best way to get better at something is to keep doing it! Hike shorter trails and easier peaks first. Baldy is challenging but during good weather (usually in the warmer months) it's a long, steep, non-technical day hike, so there isn't anything beyond just getting your legs used to those distances and elevations that you really need to train for. Good luck!

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Chris May Apr 20, 2018 13:04In reply to: Casey Schreiner

How would I get the training to try it? Is there an REI class or would I need to build up to it by doing lower level difficulty hikes in like conditions.

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Casey Schreiner Mar 14, 2018 08:03In reply to: Jeremy Wells

Jeremy,

You can hike those peaks now, but know that they are significantly increased in difficulty and require extra equipment you wouldn't need in the warmer months. I would not recommend doing either of those hikes without crampons / snowshoes (depending on the snow level), an ice axe, and the training to know how to use them. People can and have died attempting these tough day hike trails in winter conditions.

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Jeremy Wells Mar 11, 2018 16:03

Hey everyone. I hiked Cucamonga a few months back so I'm thinking of hiking Ontario Peak instead.

My question is, is it safe to hike Ontario this time of year?
And what about Mount Baldy?

Thanks in advance for your help.
Hike on!

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Stefanie Jul 14, 2017 15:07In reply to: Casey Schreiner

Thank you thank you!

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Casey Schreiner Jul 14, 2017 11:07In reply to: Stefanie

If you have an "America the Beautiful" pass, it's good on *almost* every piece of federal land that requires a day-use fee, including in the Angeles National Forest / San Gabriel Mountains National Monument!

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Stefanie Jul 14, 2017 11:07

This may be a stupid question, but is the adventure pass to hike baldy the same as the annual pass I have to the national parks? I've been trying to figure this out and I feel like a moron. Help!

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