Route 1 (MBTA)

Route 1 is a local bus route in Boston and Cambridge, Massachusetts, United States, operated by the Massachusetts Bay Transportation Authority (MBTA) as part of MBTA bus service. It operates between Harvard Square and Nubian station, primarily along Massachusetts Avenue. A major crosstown route, it is among the highest-ridership routes in the system, with service every 15 minutes or less during all operating hours.

The West End Street Railway began operating a crosstown through route between Harvard Square and Dudley Square (now Nubian Square) in 1896. Most portions of the route had originated as opened by three companies between 1856 and 1887, while the Harvard Bridge opened to streetcars in 1892. The Boston Elevated Railway (BERy) extended the line to North Cambridge carhouse by 1907 but cut it back to Harvard Square in 1912.

Traffic congestion on Massachusetts Avenue prompted several changes to the route in the 1930s, culminating in a 1936 split into Harvard–Massachusetts and Massachusetts–Dudley routes. The Harvard–Massachusetts route was partially operated with buses in 1939–1942 and 1946–1949. It was converted fully to buses in 1949, then to trolleybuses from 1950 to 1961. Off-peak service on the Massachusetts–Dudley route was converted to buses in 1948; peak service was converted in 1953. The two routes were merged into a Harvard–Dudley route in September 1962. It was designated route 1 later that decade.

Route 1 was temporarily rerouted over the Boston University Bridge from 1983 to 1987 during rebuilding of the Harvard Bridge. It was rerouted in 1987 to serve Boston City Hospital (later Boston Medical Center). The MBTA added crosstown route CT1, a limited-stop service between Central Square and the hospital, in 1994. A number of stops were closed in 2013 to reduce travel times, while several segments of bus lanes were added beginning in 2018. A 2018–19 MBTA review of its bus system found that route 1 suffered from crowding and poor reliability. Route CT1 was merged into route 1 in 2019.