Southern California's Mount San Antonio, more commonly referred to as Mount Baldy, is the dominant peak overlooking much of Orange County and the Inland Empire. Standing at 10,064 feet, it is the tallest peak in the San Gabriel Mountains, and it is visible from the coast on a clear day.
Its stature, along with its proximity to the populated region, means that its slopes can see large crowds, especially on summer weekends. However, it rewards those making the 3,800-foot climb with panoramic views of the metro area and beyond to the neighboring San Bernardino Mountains, the distant San Jacinto Mountains, the western Mojave Desert, Antelope Valley, and southern tip of the Sierra (on a clear day).
Of the options to hike to the top of Mount Baldy, the Devils Backbone Trail tends to be the most popular. (It's also possible to combine this trail with the Baldy Ski Hut Trail to create a loop.) One reason may be the year-round restaurant in the ski area sitting at Baldy Notch, an area 1,400 feet and just over 3 miles from the trailhead that makes for a great place to take a break or grab a drink on your return hike. (Hikers may also opt to purchase a lift ticket for the ski lift that typically operates on summer weekends to shave this portion of the trail from their hike.)
Nearing a short spur trail to San Antonio Falls shortly in, hikers may also keep this in mind for when they return following their 3,800-foot climb to the summit for a place to cool off in the cold year-round flow.
The trail follows a fire road that goes from unspectacular to increasingly scenic and shady once it rises above Baldy Notch. Once leaving the boundaries of the ski area, the trail turns into a narrow track that begins to climb the Devils Backbone, a ridge that appears as a spine rising toward the summit. The climb stays steady until the route approaches the final half-mile to the peak, where steep switchbacks are carved out of the scree. The trail weaves between views of the bare Baldy Bowl and the cascading outline of the San Gabriels stretching toward Los Angeles and the forested shallower northern slope.
One last push up the loose-stone path brings you to the summit, a bare and very-windy plateau. A light jacket might be useful here as the windy conditions and extreme elevation bring a significant temperature change over even just a mile below.
The Devils Backbone Trail is about 6.5 miles each way. Incorporating the Ski Hut Trail into a loop would shave off about 2.5 miles. However, be wary that trails are hard to follow on the stone surface, and taking the wrong one may necessitate steep backtracking. Be prepared if this is your plan.
The resort at Baldy Notch offers an entertainment schedule and drink-themed promotions that may be worth looking into to include in a day trip plan.
Adventure Passes and wilderness permits are available at the Mount Baldy Visitor Center (909.982.2829), though the visitor center seems to keep extremely unreliable and sporadic hours. Mount Baldy Trout Pools, located about a quarter-mile up the hill from the visitor center, also sells Adventure Passes.
Aside from a bar, there are next to no services in Mount Baldy Village. Make sure you pick up all of your supplies before leaving the metro area and heading up the hill.