On November 27, something exciting is rolling into the Colorado Model Railroad Museum.

What is a Big Boy Steam Engine? According to Union Pacific, it's their largest steam engine, closer in length to a Boeing 747 than to a diesel locomotive. There are seven Big Boys left, and if you're a train enthusiast, put Big Boy 4014's arrival on your calendar.

To celebrate the transcontinental railroad's 150th anniversary, Big Boy 4014 (the world's ONLY operating Big Boy locomotive) will be in Greeley on November 27. You can learn more about the event and RSVP right here.