CHEYENNE (WNE) — Union Pacific’s legendary Big Boy No. 4014, the world’s largest operating steam locomotive, is steaming up for the western leg of its coast-to-coast tour to celebrate America’s 250th birthday with 27 whistle-stops and four public display days scheduled during its journey across four western states.

Details of the eastern leg of the coast-to-coast tour — including whistle-stops and public display days — will be released at a later date.

Four public display days are planned for this mighty steam locomotive during the western leg of the tour, with two days each in Roseville, California, April 10-11, and Ogden, Utah, April 18-19.

Rail fans and others are urged to order their 2026 Big Boy souvenirs early at Union Pacific’s store, mypromomall.com/unionpacific, where they can find T-shirts, hats and other merchandise.

Big Boy will leave its home base in Cheyenne on March 29, traveling across Wyoming, Utah, Nevada and California, where it will stop near historic Mile 0, the site where Central Pacific Railroad laid the first rail ties for the transcontinental railroad in 1863.

In addition to the public display days, rail fans can see this historic machine in action at whistle-stops in communities along its journey. Whistle-stops are generally 15 to 30 minutes long. Complete details of the western leg schedule can be found at UPsteam.com.

The Big Boy will make the following stops in Wyoming:

March 29 — Laramie

March 29 — Medicine Bow

March 30 — Wamsutter

March 31 — Rock Springs

April 1 — Green River

April 21 — Green River

April 23 — Point of Rocks

April 23 — Wamsutter

April 24 — Medicine Bow

April 24 — Laramie