The Illinois Railway Museum is in Union, Illinois, a town sixty mile northwest of Chicago and thirty miles east of Rockford. It is the largest rail museum in the United States. The Illinois Railway Museum was founded and is still run primarily by volunteers. They have made it their mission to educate the public about the role that railroads have played in both Chicago's history as well as the development of the entire United States. They have done this by preserving electric and steam locomotives on over 1.5 miles of enclosed track and 6 miles of open track in their ever expanding museum.

The idea for the museum was first conceptualized in 1941, when a group of Chicago volunteers wanted to save some historic electric rolling stock. For the next twenty years they collected and preserved select electric locomotives and eventually, in 1964, opened the Illinois Railway Museum on its present site. The museum still works to restore old trains to their original working condition, and if this is not possible, to a cosmetic condition similar to their original manufacture.

The Illinois Railway Museum hosts many special events to bring in the all ages of the public. In the summer of 2009, they are featuring A Day Out With Thomas. This event is geared toward preschoolers, Thomas the Tank Engine's primary fans.

If you plan to visit the Illinois Railway Museum, it is best to go on a weekend in the summer. At that time the both electric and steam engines will be running. The museum is open 7 days a week, but check their website for daily timings and the availability of attractions.