Big Boy Train Tour Schedule 2024. 4014, the world’s largest operating steam locomotive, will travel during the heartland. — union pacific will send big boy no.

4014, the world’s largest steam locomotive, will return to the rails in 2024 for a tour celebrating the railroad’s deep. Union pacific has released a detailed schedule for “big boy” 4014’s upcoming tour across wyoming, utah, nevada, california and idaho in july, including a public excursion over the legendary donner pass.