San Bernardino National Forest maintains Tool Box Springs Yellow Post Campground on Thomas Mountain, roughly 30 to 45 minutes up a fire road from the base. The drive itself is a significant factor in planning a trip here. Multiple reviewers flag that the road can become heavily rutted and muddy after rain or snow, and at least one camper without high clearance spent an hour and a half covering six miles while still scraping the undercarriage. Four-wheel drive is not technically required in dry conditions, but high clearance is consistently recommended across reviews.
The campground has around five designated sites, spaced well apart from each other, with fire rings and picnic tables at most spots. Pit toilets and trash cans are located at the start of the area, which means they can be a walk from some sites. There is no water on-site, so campers need to bring enough for drinking, cooking, and extinguishing fires. Cell service is spotty but has worked for some visitors. "Raccoons in the night, gray squirrel, other squirrels, many birds," notes Rhyn E., who camped over Labor Day weekend and found only one of five sites occupied.
Insect pressure is a real consideration in summer. Flies swarm during warmer months and can be intense enough to cut a trip short, as one reviewer discovered after abandoning a planned two-night stay. Spring and fall tend to bring fewer insects and more manageable temperatures, though nights at elevation can get cold regardless of season.
The Ramona Trail starts and ends directly behind the washhouse, giving hikers a trailhead right from camp. Nearby, Tool Box Springs Yellow Post Sites and ToolBox Springs Yellow Post 8 provide additional dispersed options along the same ridge for groups or those who want more separation. Campers planning a longer stay in the region can also browse places to camp around San Bernardino National Forest to compare nearby alternatives.
As TR puts it, "getting up Thomas Mountain is good fun," but the road condition varies considerably by season. Check recent reports before heading out in early spring, and bring extra water regardless of when you go.
RV Road Trip Guides
Map & DirectionsTool Box Springs is located in California near Anza
Coordinates
33.61173295324272 N
116.66184373521286 W
Connectivity
- T-MobileLTEGood CoverageVerified by 24 usersLast on 7/17/26
- VerizonLTESome CoverageVerified by 4 usersLast on 7/17/26
- AT&T5GExcellent CoverageVerified by 2 usersLast on 5/19/26
Connectivity
- T-MobileLTEGood CoverageVerified by 24 usersLast on 7/17/26
- VerizonLTESome CoverageVerified by 4 usersLast on 7/17/26
- AT&T5GExcellent CoverageVerified by 2 usersLast on 5/19/26
Access
- Drive-InPark next to your site
Site Types
- Tent Sites
- Standard (Tent/RV)
- Dispersed
- Group
Features
For Campers
- Trash
- Picnic Table
- Toilets
- Alcohol
- Pets
- Fires
FREE established camping
Enjoy camping on government land. Limited or no services at this camping area.
PERMIT might be REQUIRED
We curate permit requirements across the US for our PRO members. Try PRO to see if Tool Box Springs - Yellow Post Campground needs a permit.
Drive Time
- 1 hr 41 min from San Diego, CA
- 2 hrs 8 min from Los Angeles, CA
- 2 hrs 11 min from El Centro, CA
- 3 hrs 9 min from Yuma, AZ




















