The Borax Visitor Center in Boron, CA overlooks California’s largest open-pit mine and the largest borax mine in the world.

Visiting the Borax Visitor Center in Boron, CA was on my to do list for years, but I always passed it over as I searched out more exciting adventures in the Mojave Desert. Not this time.

In order to reach the visitor center you have to travel along Borax Rd. which is also one of the main roads into the mine. As with any large industrial facility, reminders about safety can be found everywhere.

Even the speed limit signs along Borax Rd. were created in the name of safety. Since huge trucks share the road with travelers on their way to the visitors center, the company purposely made the speed limit signs larger than normal and used odd numbers such as 37 1/2 and 23 MPH in order to make it harder for the drivers to ignore them.

The Borax Visitor Center sits atop a massive tailings pile that was created from the actual mine that is still active to this day.

The Visitor Center is open seven days a week from 9 a.m. to 5 p.m. (last entry at 4:45 p.m.), excluding major holidays and weather permitting. Admission is free, but all donations support local community organizations through their nonprofit foundation. Parking is accessible to recreational vehicles.

Outside the museum is a restroom and several interesting exhibits.

Twenty-mule teams were teams of eighteen mules and two horses attached to large wagons that ferried borax out of Death Valley from 1883 to 1889. They traveled from mines across the Mojave Desert to the nearest railroad spur, 165 miles away in Mojave. The routes were from the Harmony and Amargosa Borax Works to Daggett, California, and later Mojave, California.

After Harmony and Amargosa shut down in 1888, the mule team’s route was moved to the mines at Borate, 3 miles east of Calico, back to Daggett. There they worked from 1891 until 1898 when they were replaced by the Borate and Daggett Railroad.

The wagons were among the largest ever pulled by draft animals, designed to carry 10 short tons of borax ore at a time. The rear wheels measured seven feet high, with tires made of one-inch-thick iron.

The wagon beds measured 16 feet long and were 6 feet deep; constructed of solid oak, they weighed 7,800 pounds empty; when loaded with ore, the total weight of the mule train was 73,200 pounds. The first wagon was the trailer, the second was “the tender” or the “back action”, and the tank wagon brought up the rear.

With the mules, the caravan stretched over 180 feet. No wagon ever broke down in transit on the desert due to their construction. A 1,200-U.S.-gallon water tank was added to supply the mules with water en route. There were water barrels on the wagons for the teamster and the swamper. Water supplies were refilled at springs along the way, as it was not possible to carry enough water for the entire trip. The tank water was used at dry camps and water stops.

The teams hauled more than 20 million pounds of borax out of Death Valley in the six years of the operation. Pacific Coast Borax began shipping their borax by train in 1898. A day’s travel averaged about 17 miles, varying slightly from leg to leg. It took about ten days to make a trip one way. Cabins were constructed by the company for use of drivers and swampers at the night stops.

The mine wasn’t always an open pit.

Ore Cart Stamp


This is what a 190 ton truck tire..

…from a 739 Cat truck looks like.

The Borax Visitor Center itself is a pair of large Quonset huts containing exhibits, a gift shop and a video theater.


Exhibitions examine just how important borates are, the minerals that are essential to the manufacture of dozens of familiar products, from detergents to fertilizers, heatproof glass to enamelware, ceramics to computer circuitry

“Borax at Home,” showcases shelves of consumer goods made from borates including cookware, toys, personal hygiene products, home insulation, and of course, laundry detergent.

Borates for pest control.

This giant borax crystal specimen was found in 2001 submerged in water in an underground passage shored up with timbers, which infused the normally colorless-to-white borax with a brown tint. It is thought that the specimen formed over a period of 50 years.

Borate Processing

The route from Death Valley to Mojave covered 165 miles from Harmony to the first water at Bennett’s Wells, 53 miles to Lone Willow, 26 to Granite Wells, an easy six miles to Blackwater, then a 50-mile waterless stretch to Mojave. The rugged topography and climate added to the distance to create a treacherous journey. Blistering temperatures often ran as high as 130° F (or 55° C) in summer. Work crews blasted and hammered a roadbed of sorts over this rugged wasteland — the mules and wheels of the wagons had to do the rest.

Ryan, CA which is now located in Death Valley National Park.

Registered in 1894 and first used in 1891, the 20 MULE TEAM symbol became the trademark of the Pacific Coast Borax Company — and, in turn, of Borax — and its many industrial and household products.

Heading back outside, the roof of the visitors center offers up an incredible view of the massive open pit mine.

After they finish mining a section they reshape the hill into an angle of repose like this one.

The mines processing plant located above the pit.

As a parting gift, all visitors receive a free color post card, along with four samples of Kernite, Borax, Ulexite, and Colemanite. The postcard alone was well worth the detour to this obscure Mojave Desert gem.


Borax Visitor Center

14486 Borax Rd, Boron, CA 93516