N
The N line opened on September 4, 1917, and ran from 14th Street - Union Square to Coney Island. On January 15, 1918, the train’s service was extended to have a northern terminal at Times Square - 42nd Street. The extension of the northern terminal continued when in 1957 service was extended to 57th Street - Seventh Avenue. Beginning on December 31, 1972, the N began running local during late nights, as it had been the express train on the line before. In 1976, the terminal was extended yet again to Forest Hills - 71st Avenue to replace the now discontinued EE service to that station. Just like the B train, the N fell victim to budget cuts, and for a period of time its route was changed to be a shuttle between 36th Street, Brooklyn and Coney Island. On May 24, 1987, the R and the N trains switched northern terminals, giving the N access only to the Coney Island Yard and terminating its service at Astoria - Ditmars Boulevard.
Q
The Q line opened as an addition to the BMT (Brooklyn-Manhattan Transit Corporation) Brighton Line on August 1, 1920. It was first a steam engine that ran along this line going from Prospect Park to the Brighton Beach hotel in 1878. The line was extended to run north of Prospect Park all the way down to Coney Island. When the line officially opened as part of the subway system in 1920, it ran between Prospect Park and DeKalb Avenue and used the Montague Street Tunnel to connect to Manhattan.
The line was originally designated as the 1 until the letter designation system began in 1960. In 1949, the IRT Astoria Line was taken over by the BMT and in 1950, Q service extended to Astoria - Ditmars Boulevard. On December 1, 1955, the 60th Street Tunnel gave the Q access to Forest Hills - 71st Avenue, making it the new northern terminal. Two years later during the transit strike, the train ran in two sections: Coney Island to 57th Street - Seventh Avenue and from Whitehall Street to Jamaica - 179th Street. The Q’s northern terminal would stay in Queens until 2017, when it was moved to 96th Street on the Upper East Side.
R
The R line (originally designated as the 2 until 1960) opened on January 15, 1916. The line originally ran between Chambers Street, Manhattan and 86th Street, Bay Ridge, Brooklyn. Three years later, service to Manhattan would be extended to 57th Street - Seventh Avenue. The opening of the Montague Street Tunnel allowed the trains to be rerouted to run from Queensboro Plaza, Queens to 86th Street, Bay Ridge. On May 24, 1987, the R and the N swapped northern terminals because the R did not have access to any yard. This switch allowed the R access to the Jamaica Yard rather than having it run “deadheads” (rides with no passengers) to the Coney Island Yard. After Hurricane Katrina flooded many tunnels the subway used, the R ran in two sections from Jay Street - Metro Tech to Bay Ridge - 95 Street and from Forest Hills - 71st Avenue to 34th Street - Herald Square until the tunnels were restored.
W
The W line was opened on July 22, 2001, originally meant to operate as part of the N line. It used to be the express variant of the N operating only on weekdays and late nights. It took the N’s path between Coney Island and Astoria - Ditmars Boulevard, with its evening service ending at 57th Street - Seventh Avenue. After 9/11, the damage to the N line caused it to close, leaving the W to run all the local stops on the line. During this time, the Manhattan Bridge tracks were being repaired, making the trains run through the tunnels. On February 22, 2004, the maintenance was complete, and the W switched routes to run locally between Astoria - Ditmars Boulevard and Whitehall Street in Manhattan, leaving its Brooklyn portion to be replaced by the D. The line was shortly closed in 2010 due to budget cuts but reintroduced on November 7, 2016.
