The Vivian Creek Trail is the classic — and most direct — route to the summit of Mount San Gorgonio, the highest peak in Southern California at 11,503 feet. Climbing out of Forest Falls into the rugged San Gorgonio Wilderness, this is a bucket-list adventure for fit hikers: a long, steep, lung-busting trek rewarded with sweeping summit views across the SoCal mountains and deserts.

Make no mistake, this is a serious hike. The full round trip runs roughly 17 to 18 miles with a staggering 5,400 feet of elevation gain, typically taking 10 to 12 hours as a (very long) day hike, or it can be split into an overnight backpack using the trail's three designated wilderness camps (Vivian Creek at 7,100 feet, Halfway Camp, and High Creek at 9,200 feet). It's the shortest route to the top, but also the steepest, gaining elevation relentlessly through forest and alpine terrain.

Permits and preparation are essential. A free wilderness permit is required year-round for both day hikes and overnights, available through the San Gorgonio Wilderness Association — and because this is one of the most popular trailheads, quotas fill up, so apply well in advance. An Adventure Pass or Interagency Pass is also needed to park at the trailhead.

Come ready for high-altitude effort: start before dawn, carry plenty of water and food, bring layers and sun protection (weather and temperatures swing dramatically up high), and watch for afternoon thunderstorms. The season runs roughly late spring through fall once the snow clears. Pace yourself for the altitude, pack out everything, and Vivian Creek rewards you with the rooftop of Southern California.