The World’s Largest Steam Locomotive Calls Cheyenne Home

Cheyenne has always been a railroad town. From its founding as a Union Pacific camp in 1867 to the era of diesel and beyond, the railroad has shaped nearly every chapter of this city’s story. But no chapter is more remarkable than the one written by a massive, thundering machine known simply as the Big Boy.

In the early 1940s, Union Pacific faced a formidable engineering problem: how to move enormous freight loads over the steep grades of Wyoming’s Sherman Hill and the Wasatch Mountains of Utah without slowing down or requiring extra help engines. The answer came in 1941, when the American Locomotive Company delivered the first of 25 specially designed steam locomotives so large and powerful that a worker on the shop floor simply chalked “Big Boy” on the smokestack door during construction. The name stuck.

Built exclusively for Union Pacific, each Big Boy stretched 133 feet in length and weighed a staggering 1.2 million pounds, heavier than a fully loaded Boeing 747. Their frames were “hinged,” or articulated, at the center to allow the massive engines to navigate curves along the route. For nearly two decades, these mechanical giants dominated the rails between Cheyenne and Ogden, Utah, hauling wartime freight and peacetime commerce across some of the most challenging terrain in the American West.

Of the 25 Big Boys ever built, only eight survive today, and two of them have strong ties to Cheyenne. Big Boy No. 4004 made its final run from Cheyenne to Laramie in October 1958 and was later donated to the city, where it has stood proudly on display in Holliday Park since 1963. History buffs and families can visit it there year-round for an impressive, up-close look at one of the most ambitious pieces of machinery ever built.

Then there is No. 4014, the crown jewel of Union Pacific’s heritage fleet. After logging over a million miles of service, it was retired in 1961 and spent decades on static display in California. In 2013, Union Pacific brought it back to Cheyenne, where a nine-person team at the UP Steam Shop spent six years painstakingly restoring it to full operation, hand-forging replacement parts from original designs when no modern equivalents existed. In May 2019, No. 4014 moved under its own power for the first time in nearly 60 years, becoming the world’s largest operational steam locomotive. Today, it remains based in Cheyenne and periodically embarks on tours across the country, drawing enormous crowds at every stop.

The Big Boys are Cheyenne’s most famous locomotives, but the city’s railroad heritage runs far deeper. The Cheyenne Depot Museum, housed in the city’s magnificent former Union Pacific depot, brings the full sweep of that history to life with railroad artifacts and an exceptional model railroad collection. Not far away, the Ames Monument, a 60-foot granite pyramid west of the city on I-80, marks the highest point of the original Transcontinental Railroad and stands as a quiet, enduring tribute to the ambition that built it all.

After a day exploring Cheyenne’s rich railroad legacy, Little America is the perfect place to come home to. Nestled where I-80 meets I-25, our property has its own deep roots in Wyoming’s highway and travel history, and our team is happy to help you plan your next day of exploration. Settle in for a made-from-scratch meal at Hathaway’s Restaurant, unwind in one of our spacious Wyoming Suites, and let the wide-open Wyoming sky remind you why places like this, and stories like the Big Boy’s, are worth the journey.