DENVER (KDVR) – “Big Boy,” one of the world’s largest trains, took-off Wednesday from  Denver, Colorado, and plans to stop in 10 states while on tour. It’s stops include the Union Pacific Museum in Council Bluffs, where four lucky winners of an auction that took place August 12th, will ride in the cab on September 4th, during Big Boy’s planned Heartland of America tour. The train will then make it’s way to Carroll and Boone before heading to points eastward.

The history of Big Boy started with 25 trains, each of which were 132 feet long and 1.2 million pounds. The company said all are now out of service or on display, except for one: Big Boy No. 4014.

It originally ran in 1941 and retired after 20 years and over 1 million miles. However, after a lengthy restoration, the Union Pacific Railroad says the train is now the world’s largest operating steam locomotive and is hitting the rails again.The tour runs for eight weeks.

You can see all the scheduled stops and viewing opportunities at the Union Pacific Railroad’s website. Some of them are longer display visits – planned for Rochelle, Illinois; Houston; and Fort Worth, Texas – and dozens more are short “whistle stops” or viewing opportunities. They’ve also set up a live tracker so you can watch it move across the country on tour.