自1897年至今，绿线仍在运营......
Listed below are the changes to the system by year. I refer to all lines by their present day names:
1897: The original subway opens for Green Line trolleys from Allston to Park St.
1898: Park St to North Station is opened with a trolley incline at North Station for all trolleys to the north of the city.
1901: Orange Line opens in four segments: Sullivan Sq to North Station (elevated), North Station to Dover St (Atlantic Ave elevated), Dover St to Dudley Sq (elevated), and a routing though the Green Line subway from North Station to Pleasant Ave.
1904: Blue Line opens as a trolley tunnel from Maverick Sq to Court Sq at Scollay Sq.
1906: Atlantic Ave station opens on the Blue Line.
1908: Washington St subway opens on the Orange Line, Green Line restored to trolley service.
1909: Orange Line extended from Dudley Sq to Forest Hills.
1912: Red Line from Harvard Sq to Park St opens; Green Line extended to Lechmere; Green St station on the Orange Line added.
1914: Green Line extended to Kenmore Sq.
1915: Red Line extended to Washington St.
1916: Red Line extended to South Station; Blue Line extended to Bowdoin Sq.
1917: Red Line extended to Broadway.
1918: Red Line extended to Andrew.
1919: Orange Line extended to Everett; Beach St station closes.
1921: Arlington station added to Green Line.
1922: Lechmere becomes terminal for Green Line trolleys.
1924: Blue Line converted from trolley to heavy rail.
1927: Red Line extended to Fields Corner.
1928: Red Line extended to Ashmont.; Atlantic Ave el service cut back, rush hour service only from Dudley to North Station (Dashed Line).
1929: Mattapan High Speed Line opens.
1932: Green Line extended past Kenmore with portals for Watertown, Boston College, and Cleveland Circle trolleys; Charles St station added to Red Line.
1938: Atlantic Ave elevated service ended.
1941: Huntington Ave subway opened on Green Line from Copley to Arborway.
1952: Blue Line extended to Suffolk Down.
1954: Blue Line extended to Wonderland.
1955: Science Park added to Green Line.
1959: Riverside Line added to Green Line from Kenmore Sq to Riverside.
1961: Pleasant St portal closed on Green Line.
1963: Adams Sq station closed; Scollay Sq changed to Government Center; Mechanics station changed to Prudential (All Green Line).
1965: Massachusetts station renamed Auditorium (Green Line).
1967: Orange Line stations renamed: Friend-Union > Haymarket, Milk-State/Devonshire > State, Washington/Summer-Winter > Washington, Boylston-Essex > Essex.
1969: Green Line Watertown “A” banch closed.
1971: Red Line extended from Andrew to Quincy Center.
1975: Orange Line Haymarket North extension opens from North Station to Malden Center; Charlestown elevated closed.
1977: Orange Line extended to Oak Grove.
1980: Red Line extended to Braintree.
1983: Quincy Adams station added to Red Line.
1984: Red Line extended from Harvard Sq to Davis Sq.
1985: Red Line extended to Alewife.
1987: Orange Line Southwest Corridor opened from Chinatown (renamed from Essex) to new Forest Hills; Washington St elevated closed; Green Line truncated to Heath St from Arborway.
1988: Columbia changed to JFK/UMass; added to Red Line Braintree branch.
1990: Auditorium renamed Hynes/ICA (Green Line)
2002: Silver Line Phase I: Washington St opens.
2004: Silver Line Phase II: South Boston to Logan Airport/City Point opened.
2009: Silver Line to City Point discontinued; Silver Line Dudley Sq to South Station opened.
