Ontario Peak (8,696 feet) isn’t far from Cucamonga Peak and is one of my favorite Baldy-area hikes because it sees a fraction of the foot traffic. I’ve even had the summit to myself on weekends before, a rare feat among popular SoCal hikes.
The Southern California mountain also has the advantage of being the most prominently visible peak from the Pomona Valley because it is closer to the front range than the other Baldy-area high. That means when you’re in the lowlands looking up at the mountains, there’s bragging rights to be had when pointing to Ontario and saying, “I’ve climbed that.”
Cucamonga’s smaller, wilder sister
Ontario Peak starts the same way as Cucamonga—in scenic Ice House Canyon filled with folksy cabins and the peaceful San Antonio Creek tributary. But after Ice House Saddle, you’ll break off on a signed trail heading southeast towards a ridge with epic views of the Baldy mountain area. So how long is Ontario Peak trail? Plan for about 12 miles round trip and 3,800 feet of elevation gain; even though it’s a slightly smaller mountain than Cucamonga you’re still in for a long trek.
From the saddle, you’ll travel in shaded lodgepole and sugar pine forest along a trail with a steep drop off that can get icy late in the season. After about a mile, you’ll reach Kelly Camp, named for a turn-of-the-century prospector. It was a trail resort in the 1920s and you can still see the ruins of the foundation. This also doubles as a large, flat forested camping area (if you have the proper permits), and it can get pretty crowded on the weekend.
Early in the season, there’s water from a spring, though as the temps heat up the water is less reliable. Consider filling up at Columbine Spring a mile before you reach Ice House Saddle.
Views all the way to the summit
From Kelly Camp, you’ll climb to exposed Ontario Ridge. Once on the spine of the ridge, I think those are some of the most unbeatable views of Mt. Baldy (officially, Mt. San Antonio), Timber, Thunder, and Telegraph Peaks. But the ridge is exposed and can get windy, so be sure to bring sun protection and on cooler days, sufficient warm layers.
About halfway to the summit, you’ll pass a junction with a rough use trail leading to the left towards Bighorn Peak (8,441 feet). Keep right, following the ridge on the better trail. Because you’ll hike near the tip of the ridge, it’s neat to pop your head over and look into canyons to the left and right of the trail. It almost feels like hiking in the Grand Canyon!
Towards the top, there’s a short set of switchbacks. I’ve found out the hard way they can get icy after the first snow and can stay that way later into the season. At the summit, while Ontario’s peak doesn’t have a lot of space to spread out, it makes up for it in character. Your photo choices include climbing a gnarled dead tree or scrambling out on a precarious rock cliff—both of which have amazing views of the valley below.