South Station

South Station is a transfer station on the MBTA rapid transit Red Line and bus rapid transit Silver Line, located at Summer Street and Atlantic Avenue in downtown Boston, Massachusetts. It is a part of the South Station complex, the second busiest transportation center in New England. Eight MBTA Commuter Rail and three Amtrak intercity rail services terminate at South Station; many of those passengers then transfer to the subway to reach other destinations in the city. With 24,639 daily boardings by a FY2019 passenger count, South Station is the busiest station on the MBTA subway system.
A station serving South Station was located on the Atlantic Avenue Elevated. Service on the Atlantic Avenue "El" was discontinued on September 20, 1938. The structure itself was torn down in the spring of 1942. Before stairs were added, passengers wishing to change lines from the underground station — itself opened on December 3, 1916 — had to use a paper transfer and go outside to change trains. The underground station had four staircases and one escalator leading from the surface to the mezzanine, and two exit escalators.

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