The Interior Grain Tramway was an aerial tramway built in 1901 near Pullman, Washington to move grain in sacks from the Palouse hills to the Snake River over a horizontal distance of 1,200 metres (3,900 ft) and a vertical fall of 700 metres (2,300 ft). Grain was stored in warehouses at the top and bottom of the tramway for shipment on riverboats to a railroad terminal at Riparia, Washington, 40 miles (64 km) away, with a capacity of up to 250,000 bushels per year. The tramway operated until 1938, when competition from rail service made it obsolescent. Eight of the tramways towers remain standing, and at least 27 have collapsed.