Red Line (MBTA)
Rapid transit line in Greater Boston, Massachusetts
The Red Line is a rapid transit line operated by the Massachusetts Bay Transportation Authority (MBTA) as part of the MBTA subway system. The line runs south and east underground from Alewife station in North Cambridge through Somerville and Cambridge, surfacing to cross the Longfellow Bridge then returning to tunnels under Downtown Boston. It continues underground through South Boston, splitting into two branches on the surface at JFK/UMass station. The Ashmont branch runs southwest through Dorchester to Ashmont station, where the connecting light rail Mattapan Line (shown as part of the Red Line on maps, but operated separately) continues to Mattapan station. The Braintree branch runs southeast through Quincy and Braintree to Braintree station.
The Red Line operates during normal MBTA service hours (all times except late nights) with six-car trains. The 218-car active fleet consists of three orders of cars built in 1969–70, 1987–89, and 1993–94. A 252-car order from CRRC is being built from 2019 to 2027. The Red Line is fully grade-separated; trains are driven by operators with automatic train control for safety. Cabot Yard in South Boston is used for heavy maintenance and storage; yards at Alewife, Ashmont, and Braintree are also used for storage.
Begin with the source’s own compact description: “Red Line (MBTA)” is rapid transit line in Greater Boston, Massachusetts. The dossier treats that line as a proposition to test through Line, MBTA and Rapid, not as a finished interpretation.
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Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Sep 21, 2026. The linked authority identifier is Q152039. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1969, 1987, 1993 and 2019.
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This entry incorporates text from “Red Line (MBTA)” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.