On June 17, 1973 SR 4501 pulled an excursion up the Illinois Central (Gulf) mainline to Chicago to run a few excursions out of the Windy City and then travel up to Wisconsin to pull the famed Circus Train. Central Station was closed by this time, the last trains having been transferred by Amtrak to Union Station. So it's likely that this special was the last passenger train to call at the station which was torn down a short time later.

Coincidentally, the June 17 date has other significance as well:

• June 17, 1953 - Southern runs its last regular steam-operated train (prior to the special excursion beginning in the mid-1960's)
• June 17, 1831 - In the famous story dating from the earliest days of railroading, the Best Friend of Charleston locomotive blows up when the ill-informed fireman ties down the safety valve because the sound of escaping steam annoys him.