Getting Oriented
This is the far south end of the park, past the monzogranite and the Joshua trees, in Colorado Desert country below the Little San Bernardino Mountains. The route starts at the Cottonwood Visitor Center, which is also the last building and the last ranger for the next 20 miles.
Westbound out of Cottonwood, the road is compacted and brushy, crossed by wash after wash and cut into the slope in places. At the junction with Thermal Canyon Road the route splits. South runs into Pinkham Canyon proper. West on Thermal Canyon Road is a winding wash, a short eroded climb, and more deep sand. Both canyons exit toward I-10, where frontage roads on the west side let the two ends be joined into a loop, or either canyon run as an out-and-back.
Current Status
Open as of September 16, 2026. Joshua Tree's public road-status layer listed Pinkham Canyon Road and Thermal Canyon Road as open on that date, with no closed dirt backcountry road anywhere in the park.
Park-wide fire restrictions run June 15 through October 1, prohibiting campfires, charcoal, and open flames including in the backcountry, with only self-contained gas stoves permitted. There is no seasonal gate on this road, but the park treats summer travel on backcountry roads as one more risk on top of the driving itself, and the south end of the park runs hotter than the high country around Park Boulevard.
Dirt roads across Joshua Tree close temporarily after significant rain while flood damage is repaired, and these canyons are the drainages that take the water. Driving around a locked gate is a citable offense. Current closures are posted on the park's alerts and conditions page.
Trail Overview
Of the seven backcountry roads the Park Service describes at Joshua Tree, this is the only one it calls challenging. That means rough boulders and deep sand in the canyon, a boulder pinch point in the upper canyon that may be impassable to larger vehicles, and on the Thermal Canyon side a short steep section with significant erosion, deep loose sand, and stretches where larger vehicles may be denied passage.
Wheelbase and width matter more than power here. The park's own photography of the route shows a two-door Jeep crawling down a rock waterfall mid-wash, which is a reasonable picture of what the canyon section asks for. Full-size trucks and anything with a long rear overhang should expect to turn around at the pinch.
The wash sections run deep enough that airing down is standard practice here, which means carrying a deflator and a compressor rather than planning to find one. Without a high-clearance four-wheel-drive and emergency supplies, the park says not to drive these roads at all.
The park recommends two vehicles on remote, rough roads generally, and this qualifies. ATVs, UTVs, and dirt bikes are prohibited; dual-sport motorcycles must be registered and street-legal under California law. All travel stays on the designated roadway.
Points of Interest
- The Pinkham Canyon and Thermal Canyon junction, where the route splits and the boundary marker sits.
- The rock waterfall in the canyon wash, the technical crux of the Pinkham side.
- The upper-canyon boulder pinch, which the Park Service flags as potentially impassable to larger vehicles.
- Smoke Tree Wash, the compacted westbound section out of Cottonwood, and an older name for the route in the park's road records.
Where to Camp
Camping along the backcountry roads is prohibited, which includes both canyons. No car camping, no dispersed camping, no fires, no drones.
Cottonwood Campground is the staging option, 62 sites next to the visitor center, reservable up to six months ahead. It is the only developed campground within reach of this route; the next ones north are Belle and White Tank, both well up Pinto Basin Road. Loop B at Cottonwood closes for part of the summer season.
Tips for a Safe and Enjoyable Trip
- Carry a fully inflated spare, jack, lug wrench, shovel, tow strap, traction board, and basic tools. The Park Service expects drivers here to be able to self-rescue, and warns that a rescue can take hours or days.
- Air-down gear is not optional on the wash sections. Bring a way to reinflate.
- Cell reception is very limited park-wide. The park recommends a satellite communicator.
- Fuel up before the South Entrance. There is no gas station, restaurant, or store inside Joshua Tree, and no water in the park's interior.
- Summer daytime highs run near or above 100°F, and the park advises carrying extra ice and water in case air conditioning fails.
- Travel with a second four-wheel-drive vehicle. A pinch that stops the lead rig 15 miles from pavement is a long walk otherwise.
- Leave a trip plan with someone who will notice if you are late.
- Entrance is $30 per private vehicle for seven days, $25 per motorcycle, $15 per person on foot or bicycle.
- Pets may travel the backcountry roads on a leash, but cannot go more than 100 feet from the roadway.
Fuel and Water
No fuel and no water anywhere on this route, and none in the park's interior. The Park Service states that Joshua Tree has no gas stations, restaurants, grocery stores, or hotels inside the boundary.
The Cottonwood Visitor Center is the last developed point before the route starts, and services outside the South Entrance are thin compared with the Highway 62 towns on the north side. Fill the tank before exiting I-10. The park warns that vehicles burn fuel faster in off-road conditions, and that a stranded driver may need to run the engine for climate control while waiting for help.
Nearby
- Cottonwood Spring, a palm oasis a short walk from the visitor center, with the Mastodon Peak trailhead at the same parking area.
- Black Eagle Mine Road, starting 6.5 miles north of the Cottonwood Visitor Center, 9 dead-end miles inside the park through the Eagle Mountains with some of the deepest sand in Joshua Tree.
- Old Dale Road, from the same junction as Black Eagle Mine Road, 23 miles across Pinto Basin and out to Highway 62. The climb out of the park boundary is among the most technical driving in the area.
- Cottonwood Campground, 62 sites at the south end of the park, the staging point for all three of the southern backcountry roads.
- Porcupine Wash and the Pinto Basin, north of Cottonwood on the paved road, for the drive between the park's two deserts.
