Hiking Bighorn Peak and Ontario Peak marks my sixth SoCal peak challenge after
- Climbing Strawberry Peak via Red Box Canyon
- Hiking Mount San Antonio (aka Mount Baldy)
- Hiking San Jacinto Peak from the Tramway
- Hiking Up Mt. Wilson
- Running to Mount Pinos, Sawmill Mountain, and Grouse Mountain
Whew, I can’t believe I’m finally over halfway done with all of the peaks. You can find more details about that here. This summer, our goal was to hit as many as possible that would be much more challenging in the winter. Earlier in the year, we attempted Sawmill but had to turn around due to the amount of snow (people were skiing to the top!). We hope for at least two more before the snow hits in October and November.
About Ontario Peak and Bighorn Peak
Distance: 14.3 miles
Total Vertical: 4200 feet
Gear Used:
CamelBak Zephyr 10L Running Vest Review
Honey Stinger Performance Chew Review
Tifosi Sledge Sunglasses Review
The Ontario Peak and Bighorn Peak trail starts at Icehouse Canyon (another course I want to do). Icehouse Canyon is a super busy trail and you won’t get parking at 6:30 am. We arrived at 6:30 and parked on the road about a half mile away.
Ontario Peak and Bighorn Peak Trailhead Address: 20 Ice House Canyon Rd, Mt Baldy, CA, 91759, USA.
You need the National Parks Pass or the Adventure Pass (southern California only). You can also buy a day pass at the rangers station for $5. There are bathrooms at the Ontario Peak and Bighorn Peak trailhead, and you also need to fill out a permit in the Cucamonga Wilderness (accessible). That sounds like a lot to hike to Ontario Peak and Bighorn Peak. But it’s worth it, and it’s one of the quieter trails there. All of that combined takes a maximum of 5 minutes.
You’ll hike about 5 miles until you reach the divide between Ontario Peak and Bighorn Peak. Left is Bighorn, and Right is Ontario. Then you can walk along the ridge to one or both.

My Experience hiking Ontario Peak and Bighorn Peak:
We arrived at 6:30, and all parking lot spaces were taken. We parked roughly .25 down the road. We had planned to use the bathroom, but the lines were long, so we just started hiking in icehouse canyon. I was surprised at how fast it started climbing.

You gain 600-800 feet for the first 3 miles. I like to think you get the hard part over with. During the first mile up, you see ruins from old houses. I was curious about what those were. After research, I found out they were the Icehouse Canyon Resort that burned down in 1980. We continued along the creek bed and kept climbing up.

Around 3.8 miles, you reach the junction of the Icehouse Saddle. I hoped to see Bighorn sheep on the trail, but it wasn’t my day. From about 3.8-5, you’re hiking up and up. and up. It’s steep but it’s manageable. The next section of the hike to Ontario Peak and Bighorn Peak is probably my favorite because you can see a lot of Los Angeles.
After hiking for another mile, you’ll reach Kelly Camp (which also used to be a resort). The trail turns often but is not as steep as the earlier sections. Finally, around mile 5 of the Ontario Peak and Bighorn Peak, you’ll get the option to go left or right. The left goes to Bighorn Peak, and the right goes to Ontario Peak. Straight goes off the mountain.
We opted for Ontario Peak first. Several people seem to go to Ontario, not Bighorn (I can see why). Ontario Peak felt like you had reached a peak. It’s a prominent peak with a sign and a view, whereas Bighorn, you aren’t 100% sure you reached the peak because there is no indicator of “I am here.”
Anyway, we headed towards Ontario Peak. The climb from the split to Ontario Peak isn’t terrible; you only climb about 400 feet in 1.5 miles. (versus the 600-800 feet in earlier sections) Ontario Peak is a giant pile of rocks; you’ll even see a bottle opener on the side. Of the two peaks, it was busier. There were about 15 people at Ontario Peak and none at Bighorn Peak.
After our time at Ontario Peak, we headed towards Bighorn. To get to Bighorn Peak, you hike left. The .75 trek to Bighorn Peak is steep; honestly, it doesn’t even feel like you “made it there.” I did some research and realized Bighorn Peak was a pile of rocks. It just seems anticlimactic. Don’t get me wrong, the views were great, but I always appreciate a “wow, you made it here vibe.” You can see both Cucamonga Peak and Mt Baldy, though! You can also see Saddleback Mountain, the highest mountain in orange county.

After hitting both peaks, we headed back down the way we came. One of my favorite parts of the trail is walking along the ridge between the two. You can see Los Angeles on a clear day and realize how high you are.
After that, you head back the same way you came! It feels “nice” to go downhill for 5 miles, but it also feels neverending. I could have been done at 10 miles, but that wasn’t the case.
I was a massive fan of both Bighorn Peak and Ontario Peak and the general vibe on the entire trail. I appreciate that it’s quieter than Mt. Baldy.
You can see more hikes and trail runs here.
Questions for you:
Have you done Bighorn Peak and Ontario Peak?
What is your favorite hike?