57 (MBTA bus)
| Company type | Streetcar route |
|---|---|
| Industry | Public transportation |
| Founded | 1858 |
| Defunct | 1969 |
| Fate | Replaced by MBTA bus route 57 |
Area served | Boston metropolitan area |
| Parent | Massachusetts Bay Transportation Authority (MBTA) |
The A branch, also known as the Watertown Line, was a streetcar route within the Boston metropolitan area, functioning as a branch of the Massachusetts Bay Transportation Authority (MBTA) Green Line. Its path extended from Watertown through Newton Corner, Brighton, and Allston, reaching Kenmore Square before proceeding via the Boylston Street and Tremont Street subways to arrive at Park Street station.
Portions of this route trace back to horsecar operations established between 1858 and 1880. The segment connecting Union Square to Oak Square was electrified in 1889 as a component of the Beacon Street line (now the Green Line C branch). By 1896, electric streetcar services linked Newton Corner (Nonantum Square) with downtown Boston through Brighton and Watertown. Service in Brighton was extended to Watertown by 1912. The line remained operational until 1969, when it was supplanted by MBTA bus route 57; however, non-revenue trips to Watertown Yard persisted until 1994.
Formation
The Brighton Horse Railroad, a horse-drawn street railway, commenced construction in 1858. Originating at Central Square in Cambridge, the line crossed the Charles River into Allston and proceeded through Union Square along Cambridge and Washington Streets to Oak Square in Brighton. Managed by the Union Street Railway—a holding company for the Cambridge Railroad—it began service on November 15, 1858, following resolution of a crossing conflict with the Boston and Worcester Railroad. Service frequency increased in April 1878 to run cars every thirty minutes. In 1880, an additional Brighton–Cambridge route opened via Market Street and Western Avenue. Although plans existed for an extension from Oak Square to Nonantum Square at that time, it was never constructed; nonetheless, a separate line connected Watertown to Nonantum Square.
During the late 1880s, the West End Street Railway consolidated these horsecar lines under its management. On January 3, 1889, it inaugurated its first electric streetcar service running from the Allston Carhouse (just north of Union Square) to Park Square via Harvard Street, Beacon Street, Massachusetts Avenue, and Boylston Street. Shortly thereafter, electric operations extended to Oak Square. Electrification between Watertown and Mount Auburn commenced on December 12, 1893, followed by double-tracking later in that decade. The Western Avenue line underwent electrification and double-tracking on August 18, 1896—marking the final West Boston Bridge corridor to transition from horse-drawn cars.
On May 18, 1896, new tracks were laid from Union Square eastward along North Beacon Street and Commonwealth Avenue reaching Kenmore Square, linking with existing Beacon Street tracks. By June 13 of that year, the western terminus had advanced near Newton Corner (Nonantum Square). Service from Newton traveling via Commonwealth Avenue entered the Tremont Street subway on November 8, 1897. A more extensive Nonantum Square–City Point route traversing Allston and Coolidge Corner commenced on August 4, 1900. On December 9, 1912, service expanded northward to Watertown utilizing pre-existing Galen Street tracks. Early in the twentieth century, this line also facilitated freight transport.
The Boylston Street subway opened its extension to Kenmore Square on October 3, 1914; consequently, Watertown service routed through Brighton Center was immediately shifted into this tunnel. In mid-1915, the Watertown Line became one of the first Boston Elevated Railway (BERy) routes to operate high-capacity center-entrance streetcars as trailers. Evening peak short-turn trips originating from Oak Square were lengthened to reach Watertown on February 23, 1922. The Blandford Street portal on Commonwealth Avenue west of Kenmore began operation on October 23, 1932—representing the last major alteration in routing. In 1941, this line became Boston’s initial route primarily served by PCC streetcars, replacing earlier vehicle types.
North Beacon Street line
In June 1894, the West End sought authorization to construct a streetcar line along North Beacon Street, stretching from Union Square to the border of Watertown. Shortly thereafter, the Newtonville and Watertown Street Railway obtained rights to build between and Union Square, planning to utilize West End tracks for access to downtown Boston. Despite opposition from the West End, approval was granted by the Watertown Arsenal in 1896, and construction was completed by 1898.
After operational disagreements between its parent company, Newton and Boston Street Railway, and BERy, the line commenced service in 1900. On November 18 of that year, through service connecting Watertown with the Tremont Street subway started as a branch of the Newton-Brighton route. BERy purchased the line from Newton and Boston in 1907. Notably, the segment west of Market Street remained single-tracked.
The Newton Street Railway, later known as the Middlesex and Boston Street Railway, began operating Waltham–Park Street service via North Beacon Street on February 23, 1903. In 1912, this route was altered to run through Central Square via Arsenal Street and Western Avenue, while Watertown–Park Street service continued along North Beacon Street. With the Boylston Street subway opening in October 1914, North Beacon Street’s service was scaled back to a shuttle between Watertown and Union Square, which was further truncated in 1917.
On February 23, 1922, bus service replaced the North Beacon Street shuttle. A short-lived bus route from Watertown to Arsenal Street operated during 1925–26. The Central Square–Union Square line was redirected via Western Avenue and Soldiers Field Road in December 1925. Subsequently, a new bus route along River Street was extended to Union Square in September 1926, supplanting streetcar operations. These bus routes merged in February 1933 to provide a one-seat ride; this consolidated service continues today as the route 64 bus.
Closure
Prior to the assignment of letter designations to Green Line branches in 1967, the Watertown Line operated as route 69. (The current route number 57 originally denoted short-turn trips to Heath Street on the Huntington Avenue line.) The Watertown Line was then named the "A" branch as it represented the northernmost Green Line segment. Turnaround loops existed at Union Square, Oak Square, and at the Watertown terminus. Between 1915 and 1962, a special loop at Braves Field served event-related traffic on the Commonwealth Avenue section.
The Riverside Line’s inauguration in 1959 prompted Cambridge streetcar routes to transition to trackless trolley operation, freeing PCC streetcars for deployment on Riverside. However, maintaining multiple PCC car models from the 1940s complicated fleet management amid aging equipment. By the late 1960s, deterioration of streetcars coupled with insufficient replacements led the MBTA to propose a "trial" closure of the A branch.
The A branch was chosen for discontinuation due to its extensive street-running sections between Watertown and Packards Corner and previous resistance toward extending service beyond Newton Corner. Streetcar operations ended on June 20, 1969; bus route 57 commenced service on June 21.
Track removal
Following closure in 1969, tracks remained intact to facilitate Green Line streetcar access to Watertown Carhouse for maintenance purposes. The final use occurred in 1993 when PCC streetcars destined for refurbishment on the Ashmont–Mattapan High-Speed Line were serviced there. The overhead electrified wires were dismantled in March 1994.
Most overhead wiring and track infrastructure were removed by summer 1996 during resurfacing work on North Beacon Street. Remnants of track persist at Watertown Yard bus terminal—which no longer functions as a railcar maintenance facility—and as a short track stub at Packard's Corner where the A branch diverged from the B branch. This stub served as storage for disabled trains until it was shortened in the mid-2000s; its switch was disconnected in 2014 and subsequently paved over by 2020.
Although proposals have been made to reinstate A branch service for direct downtown access from northern corridors, such plans have been dismissed due to high costs and safety concerns compared with existing bus options.
Route 57
The 57 Watertown Yard–Kenmore station bus service commenced in 1969, taking over from the A branch streetcar line. It largely traces the original path except at the Newton Corner rotary, where buses adhere to traffic flow instead of using a dedicated counterflow lane. Initially, limited-stop trips operated between Packards Corner and Kenmore to supplement local "B" branch service; however, in December 2006, the 57 transitioned to making all stops along Commonwealth Avenue.
Before January 2007, passengers boarding at Watertown paid double fares when traveling downtown because free transfers had been discontinued since 1961. This changed with the introduction of CharlieCards, which restored free transfer privileges.
Short-turn rush hour trips between Oak Square and Kenmore were eliminated in 1971 but reinstated for morning service in 1987. Additionally, morning trips running from Brighton Center to Kenmore operated from 1999 until 2013. To alleviate overcrowding starting September 1, 2008, the MBTA introduced the 57A Oak Square–Kenmore short-turn during weekday peak periods, with approximately half of rush hour trips designated as 57A; full-length service remained available during off-peak times and weekends. The Oak Square short-turns were discontinued in December 2020 except for a few school-day runs, accompanied by increased frequency on the full route.
Route 57 is a vital MBTA bus line maintaining consistent headways of 10 to 12 minutes. When combined with the 57A service, it ranked as the ninth busiest route in 2012, recording over 10,000 weekday boardings. Weekday rush hour and midday operations are based out of Albany Street Garage, while evening, weekend, and holiday services operate from Cabot Garage. An early-morning round trip designated internally as route 191 runs primarily for MBTA employees but is open to the public.
A review conducted by the MBTA in 2018–19 highlighted issues with peak overcrowding and reliability on route 57 but did not recommend immediate alterations. The proposed bus network redesign in 2022 suggested increasing frequency to at least every 15 minutes throughout operating hours. The 57A short-turn was briefly reinstated in December 2024 but was discontinued once again in April 2025.
Express buses
West of Brighton Center, two express routes provide service to downtown Boston via Copley Square:
- 501 Brighton Center–Federal Street & Franklin Street
- 504 Watertown Yard–Federal Street & Franklin Street
Express bus service from Brighton and Watertown began in July 1967 under route number 61. Over time, this route underwent several renumberings (304, then 301 and 302) reflecting its express nature before adopting the current 500-series numbers in September 1996. Route 503 was introduced later in January 2005. These routes have experienced various modifications to their routing and stop patterns aimed at enhancing operational efficiency, including adjustments to service along Cambridge Street and through Newton Corner.
During a MBTA evaluation in 2018–19, routes 501 and 503 were found to have challenges such as closely spaced stops and irregular afternoon peak schedules. Conversely, routes 502 and 504 did not exhibit significant issues. Among the recommendations was a simplification of outbound routing at Newton Corner, which was implemented in September 2019.
The COVID-19 pandemic prompted service reductions that resulted in suspending routes 502 and 503 and altering schedules for routes 501 and 504. During this period, route 504 replaced route 502 service between Copley Square and downtown utilizing surface streets. Route 501 was suspended from June through August of 2020 but resumed afterward with added stops at Copley Square.
Proposals released in May 2022 aimed to make some pandemic-related adjustments permanent by restricting routes 501 and 504 to weekday peak periods only; nonetheless, midday service on route 504 was restored by November of that year.