Hike Iron Mountain via Heaton Flats

Rate this Adventure Los Angeles East Fork

Added by Drew Robinson

  • 14 miles roundtrip with over 7000ft of elevation gain
  • Reach the summit of Iron Mountain, with great views of Mt. Baldy
  • One of the most difficult hikes in the San Gabriels

To reach the 8007 ft summit of Iron Mountain via Heaton Flats, you start from the Heaton Flats trailhead north of Azuza (2200 ft). The parking lot is completely full by 8am most weekends, with day hikers heading out on the much more popular “Bridge to Nowhere” hike. Iron Mountain is definitely a great hike if you like solitude. After starting towards Iron Mountain, you're unlikely to see many others. From the parking lot, you make your way down an access road to the Heaton Flats Trailhead. If you head right, you’ll be on your way to Iron Mountain, if you stay on the road (left), you’ll be on your way to the Bridge to Nowhere.

The trail starts out with a smooth singletrack that begins gaining instantly. The difference between the trailhead elevation and the Iron Mountain summit elevation is about 5800 ft (2200 to 8000)… but because of the roller coaster nature of the trail, the total elevation gain is 7200 ft! This is a trail that is not used very frequently, as the surrounding shrubs and brush constantly reminded me. I can’t even begin to count the number of times my skin jousted with a yucca plant and lost.

One of the major benefits to the solitude on this hike is getting to see the flora and fauna without disruption. One of the major highlights was seeing a horned lizard just after entering the Sheep Mountain Wilderness Area.

After about 4.5 miles of hiking the trail really starts to increase in steepness. There are certain sections that feel like climbing straight up a wall. To make things tougher, you have to dodge the aforementioned yucca spears and keep your footing in some shifty gravel ruts.

The final half mile to the summit of Iron Mountain is a rather enjoyable one. After climbing almost 2000 ft of elevation in the final mile of hiking, the smell of victory grows closer than ever.

The difficulty of the climb to the summit pays off with the ultimate reward. There is no bad view from the summit of Iron Mountain, with a breathtaking 360 degree vantage point in the heart of the San Gabriels.

The descent towards the parking lot is more difficult in some ways than the climb. Walking downhill is tough on the legs in the best of conditions, but with this grade and some shifty ruts, you need to move very carefully.

Pack List

  • Hiking Essentials
  • Hiking Shoes
  • At least 5L of water
  • Camera
  • Sun Protection Adventure Pass Self Issue Permit in parking lot
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Hiking, Photography

Skill Level:



Year Round


Easy Parking

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Added by Drew Robinson

trailtopeak.com // Instagram: @trailtopeak

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