Rainbow Basin: A Coat of Many Colors

Update: Since we last wrote about this lovely place, the Bureau of Land Management purchased photos from us of Rainbow Basin. You will find them on interpretive panels on trails and landmarks. Enjoy!


Rainbow Basin has a diverse landscape of hills, canyons and washes. It is accessible to the public approximately 8-miles north of Barstow, California, via Irwin Road to an unpaved easy, one-way 4.6-miles loop through the colorful basin. The basin is notable for the fantastical and beautiful shapes of its rock formations: its fossil beds, which have provided scientists with valuable information about life during the middle Miocene epoch, between 12 and 16 million years ago; and to the northeast the Calico Early Man Site.


The valley between Rainbow Basin and the Mud Mountains is stunning.


Rainbow Basin has been designated a National Natural Landmark and is a mixture of private and public land but it is managed by the Bureau of Land Management. 

On a hot, breezy day, there’s hardly anywhere else I’d rather be. The fact I’ve hardly ever seen anyone else here? Bonus.


According to Geology Underfoot in Southern California, by Sharp and Glazner, Rainbow Basin is a spectacular area of 18-13 million year-old volcaniclastic sediments and ash layers overlain by recent unconsolidated sediments. The volcaniclastic sediments have weathered to a huge variety of bright colors hence the name of the place. Now try saying volcaniclastic 3 times fast!

Mysterious Rainbow Basin offers numerous photo ops which stir the imagination.
The Mojave Desert wears a coat of many colors. Just don’t expect a Skittles rainbow. The green hue comes from copper in its natural state.

Rainbow Basin is beautiful any time of the year.  Summer is often in the triple digits. The road is dirt and gravel but well-maintained.   Accessible by most higher clearance cars and 4-wheel drive vehicles. As with all road trips, make sure you have enough gas, water and food to make the ride enjoyable and safe.

John wearing his Santa hat during a Christmas photography shoot. It’s become an annual event for our family.
New sights await you around every bend.

Different times of the day accents different shadows and colors.

Barstow Syncline


A major feature in Rainbow Basin is the unique formation called the Barstow Syncline, a “U” shaped fold in the rocks. In structural geology, a syncline is a downward-curving fold, with layers that dip toward the center of the structure. The syncline is like a wrinkle in a rug. On the north side of the basin, all the rocks dip south, and on the south side of the basin, the rocks dip north.

Surprises await just off the beaten path.

Park your vehicle to the side of the road and go for a walkabout. Hiking Owl Canyon offers many discoveries, such as lava tubes and dry water falls.

We never get tired of visiting Rainbow Basin because each time is a little different from the last.



Owl Canyon Campground is designated as an Area of Critical Environmental Concern due to landscape features and paleontological resources in the area. 

One lone Joshua Tree serves as a sentinel in Rainbow Basin.



There are no dumping facilities, or potable water on site.  Fires are not allowed outside the designated campground.  The loop is not recommended for motor homes, big rigs, or vehicles towing trailers.


Rainbow Basin never ceases to amaze. We like to ponder about the cataclysmic forces that once occurred here.


Keep an eye on the weather, as the road and washes may become flooded during cloudbursts.  If it’s recently rained, the road may be washed out in places.  Desert roads can become slick as goose snot after a downpour.  There is no cellphone service in the area.

Rainbow Basin is always at the top of my sister Dawn’s list of favorite places to go when she visits us from the East Coast.
You never know what kind of wildlife you may see crossing the road.
Rainbow Basin offers oddly shaped landscapes to marvel over.




The city of Barstow can be reached via Interstate-40, Interstate-15, Highway 247, or Route 66 (Old National Trails Highway). 

From Main Street, in Barstow, travel north on First Avenue and turn left on Irwin Road. Proceed out of town until you see the sign for Rainbow Basin. Turn left on Fossil Bed Road and follow signs either to Owl Canyon Campground or the Fossil Canyon Loop Road.  The dirt loop road returns to Fossil Bed Road just west of this entrance.

Citations and Recommend Resources




One thought on “Rainbow Basin: A Coat of Many Colors

  1. I visit it often with my dogs and we hike in the area. You’re right no one ever visits (though I never go in the Summer when school is out or on the weekends). I though have always been disappointed in it, the colors are drab (something called Rainbow Basin I expected much better than mostly grays) and look like most other areas of the desert except this one area is more exposed due to erosion.

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