Through 1958, when the Highland Branch was served by the New York Central's Boston and Albany Railroad, Riverside station was at the junction between the Highland Branch and the B&A main line (now the Framingham/Worcester Line). The MTA built a large commuter parking lot with a new brick station at the center and opened the branch to streetcar service on July 4, 1959. In 1995, new elevated platforms were built at the north end of the yard and the 1959-built station used as a bus terminal. The 1995-built platforms were raised slightly above track level; these made the station handicapped accessible when low-floor trolleys arrived in 2002.