Just south of the Pennsylvania Railroad’s Baltimore station in September 1954, GG1 4875 emerges from the B&P Tunnel with a Washington–New York mail and express train as three sister Gs wait to forward Northern Central passenger trains down to Washington. Beyond the waiting Gs, under the Baltimore & Ohio’s plate-girder bridge, Pennsy P5b 4702, the Baltimore tunnel helper, stands ready for its next assignment. H. N. Proctor photo
