A 1956-built ex-B&O RDC on Thomas Viaduct, which connects Elkridge to Relay. Note the 15-foot high obelisk on the Relay side, erected by builder John McCartney; one side is inscribed- "The Thomas Viaduct, Commenced July 4, 1833 Finished, July 4, 1835."
From B&O RDCs to MARC bilevel coaches pulled by electric locomotives and diesels, the Maryland commuting scene has evolved, while trolleys, aka light rail vehicles, are back.
