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The station opened on September 10, 1932, as part of the city-operated Independent Subway System (IND)'s initial segment, the Eighth Avenue Line between Chambers Street and 207th Street. Construction of the whole line cost $191.2 million (equivalent to $4,269.8 million in 2023. While the IRT Broadway–Seventh Avenue Line already provided parallel service, the new Eighth Avenue subway via Central Park West and Frederick Douglass Boulevard provided an alternative route.
This underground station has two local tracks with two side platforms. The two express tracks, used by the A train during daytime hours, are on a lower level beneath the station and are not visible from the platforms.
The station once had a southern mezzanine with exits to 153rd Street, but it is now closed and used as a MTA New York City Transit facility. The north end at 155th Street has vent chambers and a high ceiling.
Like several other IND Eighth Avenue Line local stations, this station does not have a trim line, but does have mosaic name plates reading "155TH ST." in white sans-serif lettering on a yellow background with black border. Small tile captions reading "155" run along the wall at regular intervals between the name tablets, and beneath the name tablets are directional captions, all white lettering on a black background.
The trim line was part of a color-coded tile system used throughout the IND. The tile colors were designed to facilitate navigation for travelers going away from Lower Manhattan. As such, the yellow tiles used at the 155th Street station were originally also used at 145th Street, the next express station to the south, while a different tile color is used at 168th Street, the next express station to the north. Yellow tiles are similarly used at the 163rd Street–Amsterdam Avenue station, the only other local station between 145th Street and 168th Street.
Exits
This station has pairs of staircases leading to the northwestern, northeastern, and southwestern corners of St. Nicholas Avenue and West 155th Street.
Note: Service variations, station closures, and reroutes are not reflected here. Stations with asterisks have no regular peak, reverse peak, or midday service on that route. See linked articles for more information.
Stations and line segments in italics are closed, demolished, or planned (temporary closures are marked with asterisks). Track connections to other lines' terminals are displayed in brackets. Struck through passenger track connections are closed or unused in regular service.