The 1 Broadway – Seventh Avenue Local is a rapid transit service in the New York City Subway's A Division. Its route emblem, or "bullet", is colored red since it uses the IRT Broadway – Seventh Avenue Line for its entire route.
The 1 operates local at all times between Van Cortlandt Park – 242nd Street in Riverdale, Bronx and South Ferry in Lower Manhattan.
When the first subway opened between 1904 and 1908, one of the main service patterns was the West Side Branch, which the modern 1 train uses. Trains ran from Lower Manhattan to Van Cortlandt Park via what is now the IRT Lexington Avenue Line, 42nd Street Shuttle, and IRT Broadway–Seventh Avenue Line.
On June 3, 1917, the first portion of the Broadway–Seventh Avenue Line south of Times Square–42nd Street (to 34th Street–Penn Station) opened; a separate shuttle service between Times Square and 34th Street was placed into service.
On July 1, 1918, the 1 was rerouted south of 42nd Street from the IRT Lexington Avenue Line to serve the rest of the IRT Broadway–Seventh Avenue Line at all times to and from the South Ferry loops.
An attempt was made to extend express service further north on January 14, 1955, when alternate rush trains ran express between 137th and 96th Streets in the peak direction. This proved unsuccessful, and ended on June 28, 1956.
Under a $100,000,000 rebuilding program, increased and lengthened service was implemented during peak hours on the 1 train. On February 6, 1959, 1 trains began to run between 242nd Street and South Ferry all times. Trains began to be branded as Hi-Speed Locals, being as fast as the old express service was with new R21s and R22s on the line. During rush hours in the peak direction, alternate trains, those running from 242nd Street, made no stops except 168th Street between Dyckman and 137th Streets in the direction of heavy traffic. The bypassed stations were served by locals originating from Dyckman Street.
PM rush local/express service was discontinued on February 2, 1959, and morning rush express service was revised on January 8, 1962 to running non stop from 225th to Dyckman Streets and 168th to 137th Streets. This express service was discontinued on May 24, 1976, after which all 1 trains began to make all stops.
On August 21, 1989, the 1/9 weekday skip-stop service started. The plan was to have skip-stop service begin north of 116th Street–Columbia University, but due to criticism, most notably that riders did not want 125th Street to be a skip-stop station, skip-stop service operated north of 137th Street–City College between the hours of 6:30 am and 7:00 pm. All 1 trains skipped Marble Hill–225th, 207th, 191st and 145th Streets, while all 9 trains skipped 238th, 215th, Dyckman and 157th Streets. On September 4, 1994, midday skip-stop service was discontinued, and 191st Street was no longer a skip-stop station.
After the September 11 attacks, 1 trains had to be rerouted since the IRT Broadway–Seventh Avenue Line ran directly under the World Trade Center site and was heavily damaged in the collapse of the Twin Towers. It ran only between 242nd Street and 14th Street, making all stops north of and express stops south of 96th Street. The skip-stop service with the 9 train was suspended. On September 19, after a few switching delays at 96th Street, service was changed. 1 trains made all stops between 242nd Street and New Lots Avenue via the Clark Street Tunnel, the IRT Eastern Parkway Line, and the IRT New Lots Line to replace 3 trains (which terminated at 14th Street) at all times except nights, when it terminated at Chambers Street in Manhattan instead. On September 15, 2002, 1 trains returned to the South Ferry Loop and 9 skip-stop service was reinstated. But Cortlandt Street, which was directly underneath the World Trade Center, was demolished as part of the clean-up and was to be rebuilt as part of the World Trade Center Transportation Hub. The MTA agreed to pay the Port Authority of New York and New Jersey (PANYNJ) to rebuild Cortlandt Street station directly under Greenwich Street and the 9/11 Memorial as part of the World Trade Center Transportation Hub. The tracks were walled off for the protection of the workers while construction took place. As a result of the massive excavation in the World Trade Center site, the 1 train used an enclosed elevated structure briefly when passing the site of the station. The station was reopen on June 28, 2010, with a connection to the World Trade Center Transportation Hub and a free transfer to the Cortland Street station on the BMT Broadway Line, the World Trade Center station on the IND Eighth Avenue, and the Fulton Street transfer complex station.
9 train service was discontinued on May 31, 2005 and 1 trains now makes all stops at all times. The skip-stop service made less sense by 2005 because of the increased number of trains being run and higher ridership at the bypassed stations; the MTA estimated that eliminating skip-stop service only added 2 1⁄2 to 3 minutes of travel time (for passengers at the northernmost stations at 242nd Street and 238th Street) but many passengers would see trains frequencies double, resulting in decreased overall travel time (because of less time waiting for trains).
On March 16, 2009, the new South Ferry station opened, replacing the original loop station. However, Hurricane Sandy flooded the station, requiring it to be shut down for repairs. Rector Street served as a temporary terminal for the 1 until April 4, 2013, when the 1 returned to the reopened loop station, also serving as a temporary terminal until the new South Ferry Station reopened on June 27, 2017.