Description: The Union Pacific's famous 844 steam locomotive, built in 1944, is the longest-running steam train in America. It still runs on UP's mainlines today.
Matt rides the 844 on its annual outing, taking 750 rail fans from Denver to the biggest rodeo in the world in Cheyenne, Wyoming. This train is so popular that traffic jams form along the tracks when it runs, as people "chase the train."
Studio: History Channel