Union Pacific Steam Locomotive #833 was a Northern-class steam engine known for speed. Its driver wheels were over six feet in diameter, helping it reach speeds of up to 110 miles per hour. The large smooth metal plates on the front of the engine, nicknamed "elephant ears," lifted smoke above the engine so it would not flow into the cab. #833 pulled passenger, mail, express, and high-priority freight trains through Ogden, Utah. Built in October 1939 and retired in 1957, it was steam powered and among only four Union Pacific locomotives of its type left in the world, with the other three in Cheyenne, Wyoming, and Council Bluffs, Iowa.