Jim is right, and the Aerials are indeed interesting:
Compare
1967 with
1970- if I'm interperting the imagery right, everything railroad related was more or less gone by 1970 (well, most of the bridges were there, and still are to this day, and maybe some sidings or ROW thereof).
One really puzzling thing - here's the Bing Bird view
of the area - note clearly the three former sidings coming in from the north, and going along side that grey-roofed distribution center (surrounded by truck trailers). OK, that distribution center was NOT in the 1970s image, so maybe Reading leveled everything visible in the 1967 image (including the roundhouse), the 1970 image catching this empty state, and then built the TOFC yard that Jim mentioned, also adding those sidings to the (then new I guess) distribution center. Unfortunately apparently nobody thought to fly over that area of NE Philly with a camera for another 30years, so the intervening history which I guess would cover your childhood - "It Is a Mystery!"