The 191st Street station is a station on the IRT Broadway–Seventh Avenue Line of the New York City Subway. Located at the intersection of St. Nicholas Avenue and 191st Street in the Washington Heights neighborhood of Manhattan, it is served by the 1 train at all times. It is the deepest station in the New York City Subway system at about 173 feet (53 m) below street level. Access to the station's main entrance is only provided by four elevators from the mezzanine situated above the platforms. A 1,000-foot-long (300 m) pedestrian tunnel also extends west from the station to Broadway, connecting it with the Fort George neighborhood.

The IRT Broadway–Seventh Avenue Line is a New York City Subway line. It is one of several lines that serves the A Division, stretching from South Ferry in Lower Manhattan north to Van Cortlandt Park–242nd Street in Riverdale, Bronx. The Brooklyn Branch, known as the Wall and William Streets Branch during construction, from the main line at Chambers Street southeast through the Clark Street Tunnel to Borough Hall in Downtown Brooklyn, is also part of the Broadway–Seventh Avenue Line. The IRT Broadway–Seventh Avenue Line is the only line to have elevated stations in Manhattan, with two short stretches of elevated track at 125th Street and between Dyckman and 225th Streets.