Haymarket station is an underground Massachusetts Bay Transportation Authority (MBTA) rapid transit station located at Haymarket Square in Boston, Massachusetts. It is a transfer station between the Green Line and Orange Line of the MBTA subway system, as well as a terminal for MBTA bus routes serving northern and northeastern suburbs. The two lines run parallel to each other through the station, with two side platforms for the Orange Line and a single island platform for the Green Line. The station is fully accessible. The Tremont Street subway, predecessor of the modern Green Line, opened in 1898. It had a four-track streetcar station at Haymarket. The subway was also used by the Main Line, predecessor of the Orange Line, from 1901 to 1908. The Main Line was rerouted into the Washington Street tunnel, with Union and Friend stations at Haymarket Square, in 1908. Union and Friend were renamed Haymarket in 1967. In 1971, the MBTA replaced the original Haymarket station with a new station slightly to the south. Demolition of a parking garage caused several closures of the station in 2021–2023. Station layout Because the Washington Street Tunnel was built to replace the Tremont Street subway for Main Line Elevated use – and to share the Canal Street incline – the Green Line and Orange Line are parallel and approximately the same depth at Haymarket. The Green Line, to the west of the Orange Line, has two tracks serving an island platform divided in half by a wall. The Orange Line has two tracks serving two side platforms. A sub-passage at the north end of the platforms allows transfer between the two lines. The two lines have separate primary entrances, although the sub-passage allows both lines to be reached from either entrance. The Green Line entrance is located north of Sudbury Street, under the east end of the Government Center Garage. It is adjacent to a two-lane busway off Surface Road, which can be reached by buses using the Sumner and Callahan tunnels or North Washington Street. The Green Line fare lobby is level with the platform. The Orange Line entrance is inside the Boston Public Market building south of Sudbury Street. A mezzanine level is between the street-level fare lobby and the platforms. Two elevators connect the Orange Line entrance to the two platforms, and another pair connect the platforms to the sub-passage. An elevator connects the Green Line