According to
Wikipedia, Cincinnati Union Terminal was in fact abandoned by Amtrak (for some kind of Amshack nearby), and a long process ensued to figure out future use. It became a shopping mall for a while, then was rebuilt as a Museum Center with a 1920s pipe organ in the rotunda. Since 1991, Amtrak has been back in the station - which probably makes it the only Amtrak station with a pipe organ!
Of course, a train each way 3 times a week in the Wee Hours (0130ish and 0400ish) doesn't require much space for the railroad station ... and little chance of somebody serenading the passengers with music from the pipe organ.