Twenty-mule team

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.

The twenty-mule-team wagons were designed to carry 10 short tons (9 metric tons) of borax ore at a time. The rear wheels measured seven feet (2.1 m) high, with tires made of one-inch-thick (25 mm) iron. The wagon beds measured 16 feet long and were 6 feet deep (4.9 m long, 1.8 m deep); constructed of solid oak, they weighed 7,800 pounds (3,500 kg) empty; when loaded with ore, the total weight of the mule train was 73,200 pounds (33.2 metric tons or 36.6 short tons).

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