Thomas Mountain Yellow Post Sites

San Jacinto Ranger District

San Bernardino National Forest

Free Camping on Thomas Mountain, CA

Thomas Mountain Yellow Post Sites are a series of eleven (11) campsites marked by a yellow post, all situated along the Thomas Mountain area within the San Jacinto Ranger District of San Bernardino National Forest. Each campsite is restricted to a single party of campers, with no more than eight (8) persons. All sites are first come, first serve, no reservations. Only Site #1 is suitable for full sized motorhomes and trailers, with the remaining 10 sites requiring 4WD, or cars, vans, and trucks. Small trailers are suitable for the remain 10 sites, however anything larger will have trouble navigating the tight turns, ruts, and bumps.


San Jacinto Ranger District logo

San Jacinto Ranger District

San Bernardino National Forest

District Office

Tel: (909) 382-2921

Official campground webpage


GPS: 33.6566, -116.6688

Elevation: 4,423 feet

Reservations: First come, first served

Camping Fee: None

Permit: None

Max stay: 14 days

Amenities: Fire rings, picnic tables

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Admin Staff

Admin Staff

Boondocker's Bible

Thomas Mountain Yellow Post Sites, Idyllwild, CA

How Crowded: These sites are extremely popular. Site #1 is the most popular because it’s suitable for any size RV and is close to the highway. The other 10 sites are still popular, though they are all located up along the mountain ridge.

How Noisy or Peaceful: All 11 sites are very peaceful and mostly quiet. Site #1 will have more road noise due to being close to the highway, though it’s still quite peaceful.

Cellular Phone Signal: Site #1 gets good cellular signal for Verizon, AT&T, and T-Mobile. The remaining sites get fair to average signal.

Road Conditions: Access into Site #1 is largely easy, though there are some ruts, otherwise, any vehicle can get into this site. The remaining 10 sites will require 4WD if towing a small trailer, and only a small trailer. Larger trailers will have difficulty making the tight turns. 2WD cars, vans, and trucks can easily get to the other sites, it’ll just be slow going.

Amenities Within Campground: Most of the sites, including #1, have a picnic table and fire ring. A few of the sites have a pit toilet nearby.

Cost of Camping: It’s free to camp at these sites, first come, first serve.

Campfires: Campfires are allowed during certain times when fire restrictions have been lifted. Otherwise, the entire State of California requires a campfire permit, which are free, and can be obtained online from CalFire Campfire Website.

Other Campsites Within 20 Miles Radius

Associated Documents

Motor Vehicle Use Map, San Jacinto Ranger District, Illustrates dispersed camping restrictions & OHV restrictions, (eff: January 1, 2023)

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