the Boston city limits. Traveling via Harvard Street, this bus serves Brookline and Allston, diverting to Union Square (Allston) before following Cambridge Street and North Harvard Street and terminating at Harvard Square, Cambridge. It connects Nubian station on the Silver Line to Roxbury Crossing on the Orange Line; as well as Fenwood Rd, Mission Park, and Riverway on the Green Line E branch; Brookline Village on the Green Line D branch; Coolidge Corner on the Green Line C branch; Harvard Ave on the Green Line B branch; and Harvard on the Red Line. No changes to the route were proposed in the May and November 2022 network plans. 71 The 71 Watertown Square–Harvard station begins at the Harvard bus tunnel lower level and leaves via the south exit onto Mount Auburn Street. It heads west into Watertown, ending at Watertown Square. At the Harvard end, to turn around, the bus exits the tunnel and makes a hard left onto Massachusetts Avenue and a right on Garden Street, and then turns right on Waterhouse Street and right on Massachusetts Avenue to return to the tunnel. The Watertown end has a loop on private right-of-way for turning around and picking up/dropping off passengers. September 4, 1958, was the last day of streetcar service on the 71. Trackless trolleys ran from then until March 13, 2022. In 2017, the 71 and 73 were selected for a bus rapid transit pilot program. Routes 71 and 73, along with the adjacent routes and , ran with trolleybuses (locally referred to as "trackless trolleys") for decades after all such other routes in the MBTA system had been eliminated, representing some of the last vestiges of Boston's once-extensive trackless trolley network. They were finally converted to diesel bus operation on March 13, 2022. No changes to the route were proposed in the May and November 2022 network plans. 73 The 73 Waverley Square–Harvard Station begins in the Harvard bus tunnel and runs concurrent with the 71 bus along Mount Auburn Street in Cambridge and Watertown. It leaves Mount Auburn Street to follow Belmont Street, which forms a border between Belmont and Watertown, then continues on Trapelo Road in Belmont to end at Waverley Square, looping at the Waverley commuter rail station on the Fitchburg Line. Until the 1950s, streetcars served this route. Starting in 1957, trackless trolleys provided short-turn service from Harvard to Benton Square, and the