Original service The T designation was originally used for
West End local and express trains in Brooklyn. The elevated
BMT West End Line opened in 1916, replacing the original
West End surface Line that opened in 1863 and branched off of the former
Fifth Avenue Elevated. The BMT West End Line connected to the recently opened
BMT Fourth Avenue Line subway. The new elevated line's service was originally labeled 3 by the
Brooklyn-Manhattan Transit Corporation (BMT). On June 24, 1916, 3 service began running between
18th Avenue and
Chambers Street on the
BMT Nassau Street Line via the
Manhattan Bridge and the
Nassau Street Loop. This service was extended to
25th Avenue on July 29, 1916 and
Coney Island–Stillwell Avenue on December 23, 1918. On September 4, 1917, the first part of the
BMT Broadway Line opened, and 3 service ran to
14th Street–Union Square. Chambers Street service was probably suspended until the remainder of the Nassau Street loop was completed. Service began running to the newly opened
Times Square–42nd Street station on January 15, 1918. Service began running part-time to
57th Street–Seventh Avenue on July 10, 1919, and this extension was probably axed in 1920. All express trains began running to 57th Street on May 2, 1957. On October 24, 1957, late night service was replaced by locals to Chambers Street, running via the tunnel in both directions, and terminating at
Coney Island–Stillwell Avenue. Express service was eliminated during middays, being replaced by locals extended to Coney Island on May 28, 1959. At this time all locals to Chambers Street began running via the tunnel in both directions.
Post-Chrystie Street Connection rollsign The T was discontinued on November 26, 1967, after the
Chrystie Street Connection opened. This connection linked the new express tracks of the
IND Sixth Avenue Line to the
Manhattan Bridge, allowing for increased subway service between Brooklyn and
Midtown Manhattan. As a consequence, the connection between the Nassau Street Line and the Manhattan Bridge was severed, ending the Nassau Street Loop in Lower Manhattan. The
BB, a Sixth Avenue Line service which formerly operated solely in Manhattan, was now extended to Brooklyn via the Manhattan Bridge, running along the BMT Fourth Avenue Line and BMT West End Line to Coney Island. This new B service replaced T and TT service into Manhattan. However, late-night and Sunday shuttle service between Coney Island and 36th Street was still labeled TT. The new color scheme for subway routes introduced that day included a blue TT bullet. On July 1, 1968, the TT designation was discontinued entirely with late-night and Sunday shuttle service labeled B instead. The TT's route via the BMT Nassau Street Line was replicated in 1987, when the
M was rerouted from the Brighton Line to the West End Line running to Bay Parkway. The M ran on the BMT Nassau Street and West End Lines on weekdays until June 25, 2010. The Manhattan Bridge's north side tracks closed for repairs again on July 22, 2001; B service in Brooklyn via the Sixth Avenue Line was replaced by the new service, running via
Broadway express to Astoria-Ditmars Boulevard, essentially recreating the T route once again. This lasted until February 22, 2004, when, following the completion of repairs to the Manhattan Bridge, the was rerouted over the West End Line, providing full-time service via Sixth Avenue Express, which continues today. The T bullet appeared on some
rollsigns on older railcars as a black letter on a white circle. The T was programmed into R44 and R46 side signs as a West End route, with various Broadway, Sixth Avenue and Nassau Street designations. ==Planned Second Avenue Subway service==