Union Pacific Big Boy: The Behemoth Train that Tamed the Rockies

The Union Pacific Big Boy was the largest, most powerful steam locomotive engine the world had ever known.

Built between 1936 and 1944 , the Challenger steam locomotives were the reliable workhorses of the Union Pacific .

The design of the Big Boy essentially involved expanding and improving certain sections of the Challenger locomotive, most notably the number of wheels and enlarged firebox, the area where the fuel is burnt.

The locomotive and it's tender together weighed 604 tons , which, and this will blow your mind, is roughly the same as 2 early model 747 passenger airliners.

Each locomotive cost $ 265,000 to build, which is around 4.6 million today .

The locomotives had a maximum speed of 130 kilometers an hour , but rarely if ever reached that while pulling freight.

Big Boy # 4000 was the 1st to make the journey W it couldn't travel under its own power because no railway in the East was designed for such a locomotive.

The story goes that an Alco machinist scrawled the words on the engine before it departed from the New York factory, and the name immediately stuck.

To this day it remains the largest, most operational steam locomotive in the world.