The ‘World’s Largest Steam Locomotive’ is set to roll through Colorado this fall.

It’s full steam ahead for the Big Boy 2021 Tour, set to hit the rails with displays beginning in Fort Worth, Texas on Saturday, August 14th. After weeks spent traveling, the train will eventually stop in Denver, Colorado on Monday, September 6th.

As part of the 10-state tour, Union Pacific’s Big Boy No. 4014, will make several brief whistle-stops along the way in Arkansas, Illinois, Kansas, Louisiana, Missouri, Nebraska, Oklahoma, and Wyoming.

No. 4014 is the largest and most powerful operational steam locomotive in the world, according to Union Pacific. The Big Boy measures in at 17 feet tall and 133 feet long, which is about 99 feet shy from a Boeing 747.

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The locomotive was retired in December 1961 after traveling more than 1,000,000 miles in its 20 years of service.

Twenty-five Big Boys were exclusively built for Union Pacific in 1941 to handle steep terrain between Cheyenne and Ogden. Today, only 8 of these locomotive trains remain.

“Weighing in at 1.2 million pounds, the Big Boy makes a big impression in communities it visits, reminding us of bygone days and the important role the railroad continues to play in our global economy,” said Scott Moore, senior vice president – Corporate Relations and chief administrative officer.

There are currently seven Big Boys on display across the country, with viewings in St. Louis, Missouri; Dallas, Texas; Omaha, Nebraska; Denver, Colorado; Scranton, Pennsylvania; Green Bay, Wisconsin; and Cheyenne, Wyoming.

Editor’s Note: All schedule times and locations are subject to change. For a complete list of overnight and whistle stops, please visit https://upsteam.com.