Iron Mountain's North Ridge | TRVRS Outdoors

North Ridge Iron Mountain via Heaton Flats San Gabriel Mountains Angeles National Forest | TRVRS Apparel

Ben Broer, reaching Iron Mountain via its North Ridge.

There exists a mountain in the Angeles National Forest whose approach includes steep class 1-2 terrain for roughly 7 miles and 7,000 feet of vertical gain. Many have dubbed the trail "The hardest hike in the San Gabriel Mountains". While this is true for any 'single summit day hike' on an official (more or less) trail, there is another approach to this same Iron Mountain that is far more difficult. The route includes a half mile of dense bushwhacking, class 3 boulder scrambling over degraded granite, and over 4,000 feet of vertical gain in 2.5 miles. All of this takes place after a 7 mile approach in a canyon that features nearly a dozen creek crossings through a constantly diminishing trail flanked by poison oak. In spite of all of its difficulties, the North Ridge of Iron Mountain includes some pretty spectacular views of Fish Fork and the Pine Mountain Ridge as well as the extent of the San Gabriel River toward Mount Baden Powell.


There are a handful of cross country hikes here in the Southern California Wilderness that push the limits of the word "adventure" for several reasons. They are extremely remote locations that most people will never have the pleasure of seeing. A consequence of their isolated location is that rescue is highly unlikely in the case of an emergency. 

That being said, it is the responsibility of the few that are capable of reaching these locations to practice safety when traveling to these places.

TRVRS Outdoors is all for encouraging new and exciting adventures, but part of the adventure is doing adequate research ahead of time to assure a safe and fun trip which is why we've decided to document these back country hikes. Stay safe!

North Ridge Iron Mountain via Heaton Flats San Gabriel Mountains Angeles National Forest | TRVRS Apparel

Google Earth overview of the East Fork and Iron Mountain.

Heaton Flats and the East Fork

I met Ben at the local Starbucks to see if the Barista offered shots of espresso intravenously before we carpooled up the highway 39. The often congested Heaton Flat parking area was nearly empty at 7:00 AM and the stale morning chill was a great motivation for sticking to our plan of jogging to the bridge. We used this time to discuss the expectation ahead and with each use of the term "bushwhacking", Ben would waste no time at firing off a joke regarding his relationship with my mother. Game on. 

Beyond The Bridge to Nowhere

4.5 miles | 1,600 ft. vertical gain

The Narrow of East Fork via Heaton Flats - San Gabriel Mountains Angeles National Forest | TRVRS Apparel

The Narrows of the East Fork.

We made it to bridge within an hour knowing that every mile past this point would be more difficult than the last. Essentially all of the difficulties faced along the trail before the bridge were enhanced vastly. Poisonous plants riddled the trail, creek crossings were far more consistent and searching for the overgrown trail became second to wading through the edge of the creek bed. After an additional 1.2 miles (and 550 feet of vertical gain), we had made it to Iron Fork. We stayed to the right at this confluence to continue toward our next destination.

Fish Fork

7.5 miles | 2,800 ft. vertical gain

We had made it to Fish Fork within another hour, which meant that the 3 mile stretch between the bridge took us as long as the 4.5 mile stretch from the car. Still, we felt confident in our efforts to shave off as much time from the easy part as possible. Excited that we were doing well, I pointed at the most obvious gully to the right and decided it was the one we would ascend. We took some time to filter water before starting the climb. Twenty feet from the bottom, the large shale slabs started to slide down the slope. We carefully ascended toward the ridge and as I reached the top, I noticed that everything ahead of us was completely overgrown. I had brought us up the wrong gully. I looked back at Ben to give him the news and he was mostly just disappointed that we had to go back through the loose rock. Before descending, we made sure to get a good view of the other potential gullies ahead.

The North Ridge of Iron Mountain

8 miles | 3,000 ft vertical gain.


Ricardo Soria, navigating the Gully.

As we made it back into the canyon, I started thinking back to my first experience on this climb. I read reports stating that the correct gully was about a half mile past Fish Fork and at the time had no idea what a gully was. I started climbing a combination of visible tree roots and granite right at the edge of the ridge before finding myself surrounded by brush and realizing my error. I checked the distance and set my sights on finding the visible tree roots along the right side of the canyon. The previous setback made Ben a little more careful of trusting my navigational efforts and he moved right passed my landmark. Within a quarter mile, he asked what I was thinking and I told him I was absolutely positive that we had missed our train. We moved back toward the landmark and backtracked further to the next most obvious gully where we began to ascend.

Topographical map with route - North Rige Iron Mountain | TRVRS Apparel, topographical overview of our selected route on the North Ridge.

This gully was slightly more forgiving then the last. The worst of the scree was easily avoided and small segments of the route had the faint resemblance of a use trail. Our progress up the ridge paralleled a growth in confidence until we climbed roughly 500 feet and found ourselves engulfed in chaparral for 500 feet more. This on and off bushwhacking occurred twice over the course of a half mile until we finally reached a clearing. 

North Ridge Iron Mountain via Heaton Flats San Gabriel Mountains Angeles National Forest | TRVRS Apparel

The cliffs above Falls Gulch reached out toward the pseudo-summit while our ridge laid the path to the left. Although we had finally polished off the bulk of the chaparral, some mostly avoidable buck thorn lined the path as if to taunt us. Ahead of us were two potential routes, a lighter colored granite chute to the left and a darker series of chutes to its right. I recalled taking the option to the right during my previous ascent and we stuck to it. We could immediately tell that the steep granite was crumbly and even with our best efforts at watching our step, experienced several close calls. One particular occurrence of which included a four hundred pound boulder being displaced from the class 4 exposed chute Ben was in the middle of ascending. We were both lucky I had decided against following him moments before it happened. 

North Ridge Iron Mountain via Heaton Flats San Gabriel Mountains Angeles National Forest | TRVRS Apparel

One of the knives edge ridgelines during our class 3 ascent.

North Ridge Iron Mountain via Heaton Flats San Gabriel Mountains Angeles National Forest | TRVRS Apparel

What the hell is even happening here. This is like climbing the cliffs of insanity on the Princess Bride!

The entirety of this seemingly endless rock scramble took us about an hour and thirty minutes for a grand total of .8 miles and 2,300 feet of vertical gain which qualified the north ridge as the steepest sustained ascent I had ever made within the Angeles National Forest. 

Iron Mountain Summit to Heaton Flats

10.6 miles | 8,000 ft. vertical gain


Panoramic view of the Southern view from Iron Mountain summit.

1:00 PM -- We had reached the pseudo peak and final plateau. The adrenaline from putting the difficulties of the climb behind us combined with the panoramic view of the Ross Mountain Ridge left us overwhelmed with joy. The triangular witness post was now in plain sight and a 250 foot hike brought us to the summit at 1:15 PM. After signing the register and taking a few photos of the infamous San Antonio Ridge Traverse, we scarfed down the majority of our remaining snacks and made for the trail. Ironically, Ben had never ascended Iron before and although all that was left was a descent, we both knew that we were in for a rough landing at Heaton Flats. 

We shuffled down the steep south ridge and parts of my body I didn't know existed were now screaming at me. My knees seemed to buckle with every step and my hips felt like jello. The morning marine layer had dissipated, leaving us completely exposed to the sun. By the time we had reached the car, we were pretty toast and the summit beer we had denied ourselves at the peak during the trek was now calling to us. We had completed the North Ridge of Iron Mountain and a celebration was in order.


Total Distance: 17 miles

Total Elevation Gain: 7,500-8,500 feet. (This is our best estimate based on three GPX files uploaded to Strava, Caltopo, and Google Earth. The canyon seems to not like GPS equipment).

Trail Difficulty: Ridiculously Hard - Ben even stated that this route was harder than Triplet Rocks several times upon our completion. I'd say it was AS hard and definitely more dangerous.

  • Class 1-2 defined trail for first 4.5 miles. Use trail passed the bridge that becomes increasingly difficult to find.
  • Half mile of bushwhacking on a steep ascent. 
  • Class 3-4 degraded granite for more than a mile
  • 4,000 feet of vertical gain in 2.5 miles.
  • Rockfall is inevitable on this route even with a careful team. Helmets advised. 
***If you are planning to complete this hike, please be aware of your own abilities and needs. Our completion time was roughly 9 hours, but other groups have taken up to 17 hours on this route. There is plenty of filterable water from the trailhead all the way up to the Fish Fork at which point you will need to carry everything you need for the remaining 10 miles back to Heaton Flats.



North Ridge of Iron Mountain via San Gabriel River Trail - GPX FILE
Ricardo Soria Jr. (writer) - Please read the report before using. There are two errors on this GPX file that could save you a lot of time! 

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