Operation of the first subway began on October 27, 1904, with the opening of the original 28 stations of the New York City Subway from City Hall to 145th Street on the West Side Branch including the 91st Street station. The station's decline commenced in the late 1940s when platforms on the IRT Broadway–Seventh Avenue Line from 103rd Street to 238th Street were lengthened to to allow trains of ten cars to stop at these stations; previously, platforms could only accommodate six-car local trains. The platform extensions were opened in stages through 1948. Furthermore, a new service pattern was implemented on the line during peak hours in the late 1950s, removing a rush-hour service bottleneck north of 96th Street by rerouting local trains up the Broadway–Seventh Avenue Line to Van Cortlandt Park–242nd Street and express trains to the Bronx and 145th Street via the IRT Lenox Avenue Line. On February 6, 1959, all Broadway trains became locals and all Lenox Avenue trains were expresses, eliminating the need to switch tracks. The rush-hour service could not be implemented until the platform extensions at stations on the line were completed. The original IRT stations north of Times Square could only fit five- or six-car trains. By 1958, the platform extensions at the local stations were nearly completed, but there were more problems with the platform extensions at the two express stations, 72nd Street and 96th Street. At 72nd Street, the track layout was simply changed, but at 96th Street, the local tracks and the outside walls had to be moved. A new mezzanine with stairways to the street was built between West 93rd Street and West 94th Street. The 86th Street and 96th Street stations had their platforms extended in order to accommodate 10-car trains. The 91st Street station could not have its platforms extended, because they would already be too close to the other two stations. It was closed on February 2, 1959. Advertisements from 1959 persisted for several years before the station walls were graffitied over.
Station layout
The station's two abandoned side platforms are still visible from passing trains. The 91st Street station is fairly well preserved, with the exception of some litter and graffiti.
