Union Pacific’s Huge Boy No. 4014 Runs Unassisted Through Wasatch Mountains

On April 17, 2026, Union Pacific’s No. 4014, the world’s largest operating steam locomotive, was photographed running unassisted up the Wasatch grade under bitterly cold conditions, freshly snow-capped from the previous day’s storm. The image captures the 4-8-8-4 “Big Boy” type locomotive navigating the rugged terrain blanketed with grasses and sage at lower elevations and mountain mahogany, aspen, and limber pine above, with bighorn sheep and cougar inhabiting the region.

Built in November 1941 by the American Locomotive Company in Schenectady, Recent York, No. 4014 was originally assigned to haul heavy freight trains in the Wasatch mountain range. After retirement in December 1961 following over one million miles of service, it was reacquired by Union Pacific in 2013 from the RailGiants Train Museum in Pomona, California, and restored to operation in May 2019 to commemorate the 150th anniversary of the transcontinental railroad’s completion.

As part of its 2026 Coast-to-Coast Tour celebrating America’s 250th anniversary, No. 4014 is operating on Union Pacific’s active freight network without passenger excursions, making 27 whistle-stops and four public display days as it travels from its Cheyenne, Wyoming home base to California and back. The locomotive continues to serve as a moving monument to railroad heritage, demonstrating the enduring power of steam technology on the nation’s busiest rail corridors.