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Devil's Slide to San Jacinto Peak

Riverside · Managed by Mount San Jacinto State Park (California State Parks) · Region: San Jacinto Mountains
Difficulty 65/100 · Very strenuousout and back#10ers#peak-bagging#idyllwild#pct
Distance
16 mi
Total gain
4,500 ft
Net gain
4,500 ft
Net loss
4,500 ft
Days
2–3
Permit
Required
Campfires
Campfires prohibited

Overview

The Devil's Slide Trail is the classic Idyllwild route to the top of the San Jacinto Mountains: 8 miles and 4,500 feet of climbing from Humber Park to the 10,834-foot summit of San Jacinto Peak, the highest point in the California State Park system. Two days with a camp at Little Round Valley is the standard.

Highlights

  • Standing on the highest peak in the state park system
  • The Pacific Crest Trail corridor through the summit country
  • Little Round Valley's high forest camp on the way up
  • Views from the summit across the desert to the Sierra on clear days

Logistics

  • Trailhead: Humber Park Trailhead (Devil's Slide) · parking: Humber Park at the end of Fern Valley Road, Idyllwild
  • Water: Seasonal springs at Little Round Valley and Wellman's Cienega; treat all water and confirm flow.
  • Resupply: None; Idyllwild has full services at the trailhead.
  • Shuttle: Not needed for an out-and-back.
  • Stove required: yes — no fires possible on this route

Permits

  • Agency: Mount San Jacinto State Park (California State Parks)
  • Reserve or apply on parks.ca.gov
  • Quota: Primitive wilderness campgrounds — camping permit $5 per person; check in at Idyllwild Ranger Station.
  • Reservation window: Permits issued at the Idyllwild Ranger Station; wilderness sites are not reservable in advance.

Campfires & stove regulations

Campfires prohibited. Campfires are prohibited in the state wilderness. Only portable stoves with an on/off switch are permitted. Current fire restrictions. Rules change with conditions — always confirm with the managing agency before your trip.

Best time to go

Best months: June, July, August, September, October.

Snow: The peak can hold snow into June; traction devices recommended in shoulder seasons.

Heat: Warm on the lower trail; cool above 8,000 ft.

Bugs: Minimal.

Weather forecast

Know before you go

  • 4,500 feet of climbing over 8 miles — a serious leg day
  • Campfires are prohibited; stoves only in the wilderness
  • Water is seasonal above 8,000 feet — carry plenty and confirm springs
  • Snow lingers into early summer on the upper trail

Sources & citations

Data compiled 2026 from public agency and reference sources. All descriptive text on this page is original; verify current conditions with the managing agency before your trip.

  1. Hiking Trails — Mount San Jacinto State Park. California State Parks. https://www.parks.ca.gov/?page_id=30375. Accessed 2026-09-07. License: Public domain (US government work). Devil's Slide Trail to San Jacinto Peak (16.0 mi round trip, 4,500 ft elevation gain) and to Wellman Divide (10.6 mi, 3,300 ft), both requiring wilderness permits.
  2. Mount San Jacinto State Park. California State Parks. https://www.parks.ca.gov/?page_id=636. Accessed 2026-09-07. License: Public domain (US government work). Wilderness camping permit ($5/person), campfire prohibition and stove rule, dogs prohibited, and Idyllwild Ranger Station check-in.
  3. San Jacinto Peak. Wikipedia. https://en.wikipedia.org/wiki/San_Jacinto_Peak. Accessed 2026-09-07. License: CC BY-SA 4.0. Summit elevation (10,834 ft), prominence, and PCT corridor context.