Union Pacific, heavy freight locomotive 4014 "Big Boy", Heritage Edition, with oil tender, Era VI.

25 locomotives of the "Big Boys" were built for the Union Pacific Railroad and operated between Ogden, Utah and Cheyenne, Wyo.

Big Boy No. 4014 was delivered to Union Pacific in December 1941 and was retired exactly 20 years later, after covering 1,659,564 km during its 20 years of service.

In 2013, X4014 was repurchased by Union Pacific from the RailGiants Museum in Pomona, California and brought to Cheyenne to undergo a multi-year restoration process to bring it back to life.

In May 2019, it was reintroduced into service in celebration of the 150th anniversary of the completion of the transcontinental railroad.

The new Rivarossi model 2022 features a new oil tender (the actual tender comes from UP "Challenger" 3985), a modified boiler, new radio antennas, and other newly reworked details that correspond to its 87 times larger prototype.