Green Line (MBTA)

The Green Line A branch was the northernmost of the branches, running from the Blandford Street portal (still used by the B branch), west to Watertown, mostly street-running. The 57 bus replaced the streetcar line in 1969. The A branch diverged from Commonwealth Avenue west of Boston University and ran to a terminus in Watertown, across the Charles River from Watertown Square, until 1969. Although the route-letter scheme had been introduced two years prior to its closure, the "A" designation was never signed on streetcars to Watertown. It was, however, included in the destination signs on the Boeing-Vertol LRVs ordered in the mid-1970s, when reopening service to Watertown was under consideration. The "A" line tracks remained in non-revenue service to access maintenance facilities at Watertown until 1994.

No branches had used the Canal Street portal (except as a terminal) after 1949 or the Pleasant Street portal after 1961. All Green Line trains stop at Park Street, Boylston, Arlington, and Copley. All trains except "E" also stop at Hynes Convention Center and Kenmore. Only "E" trains stop at Prudential and Symphony.

The Pleasant Street portal hosted two services in its final days. The 9 to City Point ended in 1953, and the 43 to Egleston was cut back to Lenox Street in 1956, cut back to the portal in 1961, and ended operation in 1962. Prior to that, the 48 ran out Tremont Street to Dover Street and Washington Street, ending at Dudley, and last running in 1938.

The last two routes to continue beyond the Canal Street portal both ran to Sullivan. The 92 ran via Main Street, last running in 1948, and the 93 via Bunker Hill Street last ran in 1949. Until 1997 trains continued to use the portal and its North Station surface station as a terminal.

In addition to the lines that later became the E branch, the predecessors to the 58 and 60 split in Brookline, one branch running into the current "E" tracks and into the Boylston Street portal, and the other running up Brookline Street to end at Massachusetts Avenue station. These were truncated in 1932 into a shorter route from Brookline Village to the subway via the Boylston Street portal, which itself stopped running in 1938 (being cut back to Brigham Circle short-turn trips), three years before the closure of that portal.

The last "foreign" cars to operate in the subway were those of the Eastern Massachusetts Street Railway, running from the Canal Street portal to the Brattle Loop at Scollay Square until 1935. It was then that the old Mystic River Bridge to Chelsea was closed to streetcars and the lines were replaced by bus service; the next year the BERy bought the Eastern Mass Chelsea Division and through-routed it with its lines connecting to the East Boston Tunnel at Maverick.

From the Lechmere terminal opening on July 10, 1922 to February 6, 1931, special service ran from Lechmere to various points on the subway. These trips were replaced on February 7, 1931 by extensions of the various branches from the west, which had terminated at Park Street, through to Lechmere.

Cars entered the subway from the surface at a number of portals or inclines, listed here from north to south/east to west.

Lechmere was the north end of the Green Line until 2020. From the opening of the Lechmere Viaduct leading to it in 1912 until 1922, streetcar lines simply fed onto the viaduct from Cambridge Street and Bridge Street (now Monsignor O'Brien Highway). In 1922 a prepayment station was opened, with a new loop for subway trains to turn around and a separate loop for surface cars, and no intermingling between the two. The surface lines have since been replaced with buses, but the Green Line still looped at Lechmere until 2020.

Canal Street portal in 1901

The Canal Street portal (also Haymarket portal, North Station portal or Causeway Street portal, often referred to in revenue service as the Canal Street loop) was part of the transition between subway and elevated railway on the Green Line, as it transitioned from the Tremont Street subway to the Causeway Street elevated towards the Lechmere Viaduct until 2004, when the Green Line north of North Station was closed for building of a new tunnel and portal. Certain trains turned at Canal Street, while others emerged from the subway to a viaduct to Lechmere. It was, however, possible for a passenger to alight from a train at Canal Street and proceed up a series of stairways to the Lechmere Viaduct. However, most passengers desiring to continue to Science Park or Lechmere would have changed to a Lechmere signed car from a North Station signed car prior to the emergence from the central subway.

Flying junction on the Tremont Street subway approaching the Pleasant Street incline

The original four-track portal opened in 1898 at the north end of the first subway; cars could turn east or west on Causeway Street. In 1901 the Charlestown Elevated was connected to the outer tracks, and streetcars only operated via the inner tracks. The Washington Street Tunnel opened in 1908, connecting to the Elevated via a new portal just east of the streetcar one, and all four tracks were once again open for streetcar use until 1975. In 1912 the Lechmere Viaduct opened, again using the two outer tracks for an elevated line. The inner tracks continued to serve the surface, including a surface station at North Station, until 1997, when they were closed for construction of the new tunnel and the Green Line was shifted to the old Orange Line (Charlestown Elevated) portal along the way. The 93 was the last service to continue onto surface streets from the portal, last running in 1949.

The Pleasant Street portal was the south end of the Tremont Street subway, opened one month after the original subway in 1897. It split from the Boylston Street subway at a flying junction at Boylston, and another flying junction split the tunnel into two side-by-side tunnels to the four-track portal. The two west tracks rose onto Tremont Street and the two east ones onto Pleasant Street, later part of Broadway. From 1901 to 1908 the portal was only used by Washington Street Elevated trains, after which streetcar service was restored—though much of it had been cut back to Dudley for transfer to the Elevated. Until 1953 service ran to City Point at eastern end of South Boston as part of 9. The last cars ran through the portal in 1961 as part of the 43, and in 1962 a shuttle service from Boylston to the portal was ended. The portal has since been covered, but someday may become part of a new streetcar line that would partly replace access to rapid transit for southern Metro Boston neighborhoods, that had been severed from MBTA rapid transit service in 1987 with the demolishing of the Washington Street Elevated original southern section of the Orange Line. This proposed new streetcar service could go as far south as the Red Line's Mattapan station, with a northern turnaround terminus at Government Center, according to a 2012-dated proposal.[11]

Streetcars using the Public Garden portal in 1898

The first portal to open, on September 1, 1897, was the Public Garden portal, providing an outlet for the subway on the north side of Boylston Street in the Public Garden. When the Boylston Street subway opened in 1914, extending the subway west, the incline and portal were relocated to the center of Boylston Street as the Boylston Street portal. The last cars to use the portal ran in 1941 from Huntington Avenue, when the Huntington Avenue subway opened as a branch off the main subway and the portal was closed.

The Northeastern portal lies in the median of Huntington Avenue at the end of the Huntington Avenue subway, just east of Northeastern University. It opened in 1941 and carries E branch trains.

The incline was built as a wooden trestle to the street atop a level grade, as the original plans called for eventual extension of the subway; in the mid 1980s the trestle was replaced with fill (which greatly quieted the sound).

Top of the filled-in Kenmore portal

The Kenmore portal or Kenmore Square portal opened in 1914 with the extension of the Boylston Street subway westward to the east side of Kenmore Square, in the median of Commonwealth Avenue. It closed in 1932 when the subway station at Kenmore was built and two new portals were opened to the west.

The Blandford Street portal and St. Marys Street portal, in the medians of Commonwealth Avenue and Beacon Street respectively, opened in 1932 as part of the extension of the Boylston Street subway under Kenmore Square and the opening of the new Kenmore station. They are currently used by the "B" and "C" Branches respectively. The Fenway portal opened in 1959 along with the opening of the Highland branch, and provides a third exit from Kenmore, south of the St. Marys Street portal. It carries trains of the D branch.

Rolling stock as of January 2021:[2][12][13]

Year Built	Manufacturer	Model	Image	Length	Width	Fleet Numbers	Quantity
1986–1988	Kinki Sharyo	Type 7 LRV		72 ft (22 m)	104 in (2.64 m)	3600–3699	100 (81 active, all overhauled) 14 other non-overhauled cars have been scrapped. 5 overhauled cars out of service in shop for repairs.
1997						3700–3719	20 (16 active, all overhauled) 3 other non-overhauled cars have been scrapped from an auction. 1 overhauled car out of service in shop for repairs.
1998–2007	AnsaldoBreda	Type 8 LRV		74 ft (23 m)	104 in (2.64 m)	3800–3894	95 (85 active)
2018-2020	CAF USA	Type 9 LRV		74 ft (23 m)	104 in (2.64 m)	3900–3923	24

Only MBTA operated vehicles are included here, not cars from the Boston Elevated Railway (BERy) era.

Years in Service	Manufacturer	Model	Image	Length	Width	Fleet Numbers	Quantity
1976–2007	Boeing Vertol	US Standard Light Rail Vehicle		71 ft (22 m)	104 in (2.64 m)	3400–3543	144 (31 units cancelled)
1937–19851	Pullman Standard	PCC streetcar		48 ft (15 m)	100 in (2.54 m)	3000–3346	344 (2 cars scrapped before 1964)

When it opened at the end of the 19th century, the Tremont Street subway was not intended as a full-scale rapid transit line (though it was built to pre-metro standards), but to allow ordinary streetcars to bypass the worst street congestion in downtown Boston.[4][14] Operations by several different companies were eventually consolidated into the Boston Elevated Railway, which ran a mixture of car types. After receiving a test unit in 1937, the BERy began to standardize on PCC streetcars, acquiring 320 units between 1941 and 1951 plus an additional 25 in 1959 to phase out the last older cars.[12]

Front view of a Boeing Vertol LRV near the end of its life in 2005

In the early 1970s, light rail—which had largely disappeared from North America after the slow decline of streetcar systems from the 1920s to the 1950s—was reintroduced as a method of urban renewal less expensive than conventional metro systems.[15] In 1971, as part of a program to supply further work to defense contractors as the Vietnam War wound down, the Urban Mass Transit Administration selected Boeing Vertol as systems manager for a project to design a new generation of generic light rail vehicle.[16]

After a 1972 report by Prof. Vukan R. Vuchic,[17] Boston (with its older streetcar tunnel systems) and San Francisco (with a new Muni Metro streetcar tunnel being built as part of BART construction) were chosen as the testbeds for this new rolling stock, intended to jumpstart similar systems in other cities.[15] The US Standard Light Rail Vehicle was designed as the largest rolling stock that would fit through the Tremont Street tunnel, the Muni Metro's Twin Peaks Tunnel, and SEPTA's subway–surface lines tunnel.[14] The new cars were faster—a top speed of 50 miles per hour (80 km/h) versus the PCC's 36 miles per hour (58 km/h)—and had an articulated middle section for higher capacity.[14] Boeing began construction of 175 cars for the MBTA in May 1973.[16]

The first LRVs entered service on the D branch in December 1976 but were immediately beset with problems. Certain cars frequently derailed on tight turns in the Riverside, Boston College and Lechmere yards. Battery trays, air conditioners—mounted under the cars, continually drawing in dirt and debris from under the car when in the tunnels—and air compressors all suffered numerous failures; the plug-style doors had trouble sealing properly; and traction motors failed sooner than expected.[18] Desperate for reliable rolling stock, the MBTA launched an overhaul program to extend the availability of its older PCC cars. A total of 34 cars, primarily out-of-service wrecks and parts cars, were rebuilt to as-new condition.[18] In 1980, the MBTA tested Canadian Light Rail Vehicles for three months to determine whether they could be used on the Green Line.[19]

As of 2013, ten of the rebuilt PCC cars still run on the Ashmont–Mattapan section of the Red Line, because maintaining the small PCC fleet is less expensive than rebuilding the rail line for modern light rail or heavy rail stock.[12][18] Because these heritage streetcars operate exclusively on a dedicated right of way which has only two grade crossings (instead of using street running), they are less exposed to collisions in mixed road traffic.

Type 7 (left) and Type 8 streetcars at Tappan Street in 2012

Type 9 streetcar in 2018

In 1986–88, 100 second generation (Type 7) LRVs were delivered from the Japanese firm Kinki Sharyo, with an additional 20 cars ordered and delivered in 1997.[20] The first low-floor Green Line streetcars, allowing for handicapped-accessible boarding directly from slightly raised platforms, were the Type 8 cars from AnsaldoBreda which began arriving in 1998.[12] The first Type 8s entered revenue service in March 1999, but they were prone to derailment at higher speeds as well as brake problems; not until 2008 did they assume full service on the D branch (where they reach full speed).[5] One hundred low-floor cars were purchased from the Italian company AnsaldoBreda, with styling by Pininfarina. They were initially problematic and difficult to maintain: the first cars failed every 400 miles (640 km), far short of the 9,000 miles (14,000 km) specified by the MBTA, and were prone to derailments. The MBTA has been forced to spend an additional US$9.5 million to modify tracks to prevent the derailments, echoing early problems with the Boeing stock. The MBTA has been criticized for their failure to assess Bredas' reliability before entering into the deal, and during delivery.

In December 2004, the MBTA canceled orders for the cars still to be delivered as part of the authority's nine-year, US$225 million deal with Breda.[21] One year later, in December 2005 the MBTA announced that it had entered into a restructuring of the deal, reducing the order to 85 cars (with spare parts to be provided in lieu of the 15 remaining cars), and providing for the remaining payment under the original deal only if the cars met performance requirements.[22] Construction of the last car under the order was completed on December 14, 2006.[23] After additional delays on the Type 8 car order, the last 10 cars were assembled and delivered in late 2007, with five spare shells retained (95 cars in service). After several years of modifications to D branch tracks, the Breda cars returned to service on that line, and now provide service on every branch of the Green Line. As the final Type 8s were delivered, the last of the Boeing-Vertol cars were retired in March 2007 and all except ten of the cars were scrapped.[24] Of the remaining cars, six were sold to the US Government and are now in Pueblo, Colorado for testing purposes, one was given to the Seashore Trolley Museum, and three were retained by the MBTA for work service.

In 2006, as part of the settlement of Joanne Daniels-Finegold, et al. v. MBTA, the MBTA committed to always operate at least one low-floor car in each train, with no trains consisting only of Type 7 cars.[25]

Of the 120 Type 7 cars 103 were overhauled by Alstom in Hornell, New York. The work includes new propulsion systems, climate control systems and interiors as well as exterior work. The pilot car for the program left in October 2012 and was returned in November 2014, with the last car returned in April 2019.[26][12]

Twenty-four new Type 9 Green Line cars are being delivered. Revenue service began in late 2018 and all 24 cars will have entered service by the fall of 2019. The Type 9 cars will provide additional rolling stock to allow for Green Line Extension operations, and will not replace any of the existing fleet.[27] The cars will be made by CAF USA, Inc., with the shells and frames made in Spain, and final assembly and testing done at their plant in Elmira, New York.[28] As of March 2017, the first unit had been expected to enter passenger service in Spring 2018, with all 24 cars in service by the end of the year.[29] The first Type 9 car, #3900, began revenue service on December 21, 2018.[30]

Planning for a Type 10 fleet—which would likely replace all Type 7 and Type 8 cars in the mid-2020s—began in 2018 with plans for a fully low floor fleet. The MBTA released a request for proposals in December 2019, with notice to proceed expected to be given in 2021.[31] The Type 9 cars are expected to replace the PCC streetcars on the Ashmont–Mattapan High-Speed Line.[32] The Type 10 cars would be 113 feet long and carry twice as many passengers as existing cars.[32]

3295 and 5734 on display at Boylston station

Two older streetcars are on display on the unused outer inbound track at Boylston station, which formerly carried cars coming from the Pleasant Street portal. Car #5734, a Type 5 A-1 car built in 1924 and retired in 1959, is owned by the Seashore Trolley Museum, but resides semipermanently in Boston. PCC #3295, built in 1951 and retired in 1986, is owned by the MBTA.[12] The cars were formerly used for fantrips, the most recent one being in 1998. These trolleys are no longer in working condition, however. The cars were heavily vandalized on January 14, 2014, but the vandalism was fully removed the next day.[33]

The San Francisco Municipal Railway runs a variety of PCC cars in various paint schemes on its F Market heritage line. Number 1059 is painted in Boston Elevated Railway colors, but that individual car never ran in Boston.[34]

A test train on the loop at Kenmore station in 2019

Aside from the terminal stations, several locations have turnaround loops or crossover switches where trains can reverse direction for short turns. Three of these, where northbound trains can turn southbound, are regularly used as the downtown terminals for the branches:

• At North Station, a pair of pocket tracks allow reversing. As of 2020, this is the terminal of the C and E branches.
• At Government Center, a loop under City Hall Plaza. As of 2020, this is the terminal of the D Branch.
• At Park Street, a loop connects the inner tracks. As of 2020, this is the terminal of the B Branch. The MBTA plans to add a crossover to allow through movements from the terminating (inner) northbound platform at Park Street are expected to increase capacity and reliability.[41]

Several other loops and crossovers are not used in regular revenue service, but may be used during construction work or service disruptions, or for non-revenue trains:[2]

• At Government Center, the Brattle Loop allows southbound trains to turn northbound.
• At Kenmore, a loop allows eastbound (inbound) C and D branch trains to turn westbound.
• On the B Branch, a pocket track at Blandford Street allows trains to reverse in either direction. It is sometimes used to reverse westbound trains to provide extra service in the subway. Occasionally-used crossovers are located at Babcock Street, Washington Street, and east of Boston College.
• On the C Branch, occasionally-used crossovers are located at St. Marys Street and Coolidge Corner.
• On the D Branch, occasionally-used crossovers are located west of Fenway, Brookline Hills, Beaconsfield, Reservoir, Newton Highlands, and Waban. At Reservoir, the spur tracks to Reservoir Carhouse have platforms for short turn trains.
• On the E Branch, crossovers are located at Prudential, Northeastern University, and Brigham Circle, along with a siding at Northeastern. The Brigham Circle crossover is frequently used for short turns during traffic congestion on the street-running section of the line.

Map of the Green Line Extension. Nearby parts of the Red Line and Orange Line are also shown.

To settle a lawsuit with the Conservation Law Foundation to mitigate increased automobile emissions from the Big Dig, the Commonwealth of Massachusetts agreed to extend the line from its northern terminus at Lechmere to Medford Hillside through Somerville and Medford, two suburbs underserved by the MBTA relative to their population densities, commercial importance, and proximity to Boston. The line would use railroad rights-of-way that serve the Lowell Line (which also carries Amtrak's Downeaster) and the Fitchburg Line of MBTA Commuter Rail. The extension is projected to have a total weekday ridership of about 52,000.[42]

The Green Line Extension (GLX) is planned to have two branches, which will split just past a relocated Lechmere station. The Medford Branch, which will become an extension of the D branch,[43] will run along the Lowell Line right of way with stops at East Somerville, Gilman Square, Magoun Square, Ball Square, and a terminus at Medford/​Tufts in Medford, on the edge of the Tufts University campus. Earlier plans called for further extension to Route 16 or even West Medford, but extension beyond College Avenue was placed on hold due to cost issues. GLX as built will not preclude further extension to Route 16 if funding becomes available.

The Union Square branch will follow the Fitchburg Line right-of-way from Lechmere to Union Square station just south of Union Square in Somerville. It will operate as an extension of the E branch.[43]

In 2010, the Massachusetts Department of Transportation (MassDOT) announced that the new service was expected to be operational in October 2015; interim air quality offset measures would need to be taken if the project missed December 2014 deadline as expected. In August 2011, MassDOT announced that opening of the Extension would be postponed to fall (Q3 or Q4) 2018 at the earliest, with some stations not opening until 2019. The stated reason was difficulties in land acquisition, plus implied concerns about cost controls and financing.[44] Interim air-quality improvement measures will be necessary due to the project delays. Possibilities include extending Green Line branches to Lechmere, increased bus service in Somerville and Medford, and temporary or permanent commuter rail stops along the GLX corridor.[45] In September 2014, the target date for start of service was pushed back to 2020.[46]

On June 11, 2012, the Federal Transit Administration approved the Extensions for entry into the Preliminary Engineering phase as part of the New Starts program. This approval was a necessary step in MassDOT's application for $557.06 million in New Starts funding.[47]

A groundbreaking was held at the Medford Street bridge on December 11, 2012.[48] A Notice to Proceed was issued to the contractor, Barletta Heavy Division, Inc., on January 31, 2013.[49]

As of December 2015, the future of the project was in doubt due to a substantial increase in costs,[50] but it has been reduced in scope and is now expected to open in December 2021.[8]

On May 9, 2016, the GLX Interim Project Management Team submitted a report[51] outlining a redesigned project to the MassDOT Board of Directors and the MBTA Fiscal & Management Control Board, which then voted to ‘support advancing the Green Line Extension Project ("GLX Project") and [seek] Federal Transit Administration ("FTA") review and approval of the redesigned GLX Project.

To achieve needed cost savings a number of elements of the project were simplified or dropped. Stations will have open platforms with several shelters. The Vehicle Maintenance Facility will be reduced by roughly half, and three bridges that were to be replaced will instead be retained.

Under the trimmed plan, the Somerville Community Path was to terminate at Washington Street, Somerville instead of Water Street in Cambridge, however a full-length path was included in the bidding package as an extra credit option and the winning bidder agreed to build it.[52]

The FTA approved the new $2.3 billion plan on April 4, 2017. On June 25, 2018, a fourth groundbreaking ceremony was held, with local, state, and federal officials taking part.[8] The new line is expected to be completed at the end of 2021.[53]

Government Center station under reconstruction in September 2014

All of the Green Line originally opened by 1959, long before the 1990 Americans with Disabilities Act mandated that new construction be fully accessible. The MBTA began modifying Red, Orange, and Blue Line stations for accessibility in the late 1980s; however, Green Line stations were not modified until the late 1990s, when the Type 8 vehicles were under construction. The MBTA began the Light Rail Accessibility Program in 1996.[54]^:30 Because modifying the numerous stations all at once would be prohibitively expensive, the MBTA designated "key stations" – largely those with high ridership or bus connections – for prioritization.[55]

Riverside station was completely rebuilt with raised accessible platforms around 1998. North Station and Park Street (both of which already had elevators from previous projects) were outfitted with portable lifts for temporary accessibility around 2000, as were Lechmere and ten surface stations.[55] Between 2001 and 2003, 16 surface stations (4 on the B Branch, 4 on the C Branch, 3 on the D Branch, and 5 on the E Branch) were retrofitted with raised platforms.[56] The 13 B, C, and E branch stations collectively cost $32 million.[57] Construction of raised platforms was completed at Park Street and Haymarket around 2003; Prudential was also reconstructed that year by the developer of 111 Huntington Avenue. The fully accessible underground "superstation" at North Station opened in 2004.[5] Wooden mini-high platforms, allowing level boarding on older Type 7 LRVs, were installed at eleven Green Line stations in 2006–07 as part of the settlement of Joanne Daniels-Finegold, et al. v. MBTA.[25][58]

Renovations for accessibility were completed at Arlington in 2009,[59] Kenmore and Copley in 2010,[60][61] and Science Park in 2011.[62] A two-year closure of Government Center ended in 2016 with the opening of the accessible transfer station.[63] This left only Hynes Convention Center and Symphony (both with planned renovations) and Boylston as inaccessible stations in the central subway. The opening of the Green Line Extension in 2021 will add six new stations; Lechmere will be replaced by a fully accessible elevated station.

Woodland was made accessible in 2006.[64] Renovations completed in 2009 made Longwood accessible for the first time, and replaced the lifts at Boston College and Brookline Village.[65][66] Temporary work to make Newton Highlands accessible was done in 2019; a full reconstruction will be completed in 2020.[67] A reconstruction of Brookline Hills (replacing lifts) will be completed in 2021.[67] Construction of two accessible stations on the B Branch to replace four non-accessible stations will begin in 2020.[68]

Activated countdown signs at Kenmore station in August 2015

The Red, Orange, and Blue lines have block signalling systems that make tracking the location of trains easier. Signs in most station on those lines began to display real-time train information in late 2012 and early 2013, while data feeds have been available for smartphone applications since 2010.[37] However, the wayside signalling system used in the Green Line's tunnels and the D Branch does not provide for that level of tracking, nor do the basic stop/go signals used on the street-level branch lines. In January 2013, the MBTA announced plans to provide full tracking data for the Green Line by 2015, allowing use of smartphone applications and in-station countdown signs.[37] The $13.4 million system is funded by MassDOT; it uses existing Automatic Vehicle Identification (AVI) systems plus additional sensors in the tunnels, and GPS receivers on the surface sections.[69]

In September 2013, the MBTA announced that "Next Train" signs would be unveiled at Kenmore that month.[70] On October 23, 2014, location tracking data became available for Green Line trains above ground. Arrival predictions for surface stations – including the activation of countdown signs along the D branch – and underground tracking and predictions were to be rolled out in two phases by early 2015.[38] In March 2015, the MBTA announced that enough AVI equipment had been installed to allow the release of some underground data by April 2015, though some equipment would not be completed until July.[69] Most underground location data went live in August 2015, with trains near Park Street and Boylston waiting until September.

The first predictive countdown signs on the Green Line were activated at Newton Centre and Newton Highlands on April 24, 2015, followed shortly by other D branch stations.[71] Countdown signs at Kenmore and Hynes were activated in August 2015. Signs at Copley and Arlington plus eastbound-only signs from Boylston through Science Park were activated in October 2015.[72] The final set of signs – those on the westbound platforms of Science Park through Boylston – were activated in January 2016. Because holding and short-turning trains at the downtown terminals makes time-based predictions unreliable, the signs instead show how many stops away a train is.[73]