The Oak Park Society of Model Engineers, H.O Scale Model Railroad Club. Oak Park Illinois USA. September 2011., a photo by Eddie from Chicago on Flickr.
Trains that had served Chicago and other North American citties fron different eras, often operate side by side at any given operation club night session.
I grew up in Chicago during the early 1970's, and I have fond memories of the early days of the Illinois Central Gulf Railroad, which was created from the August 10th, 1972 merger of the Illinois Central, and the Gulf, Mobile & Ohio Railroads.
Scenes like this were common on the south and southwest side of Chicago in the early 1970's, with a mix of equipment from the two predescesor railroads on any given freight train.