Calumet Yard, on Chicago's south side, was the home of the last roundhouse built in the United States, completed in 1952. By this late date, NKP 173 was used as protection power for the ALCO PAs on passenger trains, as well as other miscellaneous duties such as Work trains, etc. She was kept hot in the roundhouse awaiting a call. This day she was called to handle a mail train out of Chicago and we caught her as she passed the engine terminal on her way east. It's hard to tell on this image, but she is moving fast as she passed us near the engine terminal. Image 351249 shows the train approaching. Check out that baggage/automobile car. I never saw a car like this before.