Union Pacific "Big Boy" No. 4014

This page contains photos I have taken of Union Pacific's "Big Boy" steam locomotive. It is the largest functioning steam locomotive in the world. The photos were taken in 2019 and 2021. I chased this locomotive through Texas, Oklahoma, Kansas, Missouri, and Louisiana to get these photos. Driving ahead of the locomotive's route and setting up to get a few shots before jumping back in the car and racing ahead of it to shoot it from another location on the route. Union Pacific No. 4014 is a Big Boy class steam locomotive having a 4-8-8-4 wheel arrangement. They are the heaviest single expansion steam locomotive ever built, weighing about 1,200,000 pounds. Big Boy locomotives are hinged (or articulated) because of its great length. Its forward pony trucks and drive wheels swivel independently of the boiler and rear drivers when rounding curves.