What was this building and where was it?
This certainly is a WAG, but I say it looks like the B&O Train Station
:'( Sorry my friend but its not the B&O station.
I said that because the left side looks like a portico and the building in the background looks like the old St Vincent Depaul building.
:'( Nope.
By the way John, you and City Council get a tip of the hat and a well done pat on the back for your efforts that led to the great news I posted earlier.
Pennsy station?
Answer:
The photo is of the rear of the Pennsylvania Railroad Passenger Station that was located at the Southwest corner of Spring Commons.
Here is an uncropped version of the quiz photo.