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 (275 km) 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 (9 metric tons) of borax ore at a time.
In 1877, six years before twenty-mule teams had been introduced into Death Valley, Scientific American reported that Francis Marion Smith and his brother had shipped their company's borax in a 30-ton load using two large wagons, with a third wagon for food and water, drawn by a 24-mule team over a 160-mile stretch of desert between Teel's Marsh and Wadsworth, Nevada.
20 Mule Team (aka Twenty Mule Team) is a 1940 American Western film about Death Valley, and Daggett, California borax miners starring Wallace Beery and Anne Baxter, and remains an extremely rare opportunity to watch Beery work with his nephew Noah Beery, Jr., who played "Rocky" on television's The Rockford Files 35 years later. The movie was directed by Richard Thorpe and originally released in Sepiatone, a brown and white process used by the studio the previous year for the Kansas scenes in The Wizard of Oz.