Twenty-mule team wagon on display at Harmony Borax Works. Twenty-mule-team wagons among the largest ever pulled by draft animals, designed to carry 10 short tons (9 metric tons) of borax ore at a time. Rear wheels measured seven feet (2.1 m) high, tires made of one-inch-thick (25 mm) iron. Wagon beds measured 16 feet long and were 6 feet deep (4.9 m long, 1.8 m deep); constructed of solid oak, weighed 7,800 pounds (3,500 kg) empty; loaded with ore total weight of the mule train was 73,200 pounds (33.2 metric tons or 36.6 short tons). All hauled the entire 165-mile (275km) journey across the desert to the nearest railroad spur in Mojave. Teams hauled more than 20 million pounds (9,000 metric tons) of borax out of Death Valley in the six years of the operation. Death Valley National Monument Est. February 11, 1933. Est. as Death Valley National Park in 1994; 5,270 square miles (13,649 km2). Inyo County, CA.