The West Side Branch of the first subway was extended northward to a temporary terminus of 221st Street and Broadway on March 12, 1906 with the first open station at Dyckman Street, as the stations at 168th Street, 181st Street, and 191st Street were not yet completed. This extension was served by shuttle trains operating between 157th Street and 221st Street until May 30, 1906 when express trains began running through to 221st Street. In 1948, platforms on the IRT Broadway–Seventh Avenue Line from 103rd Street to 238th Street were lengthened to to allow full ten-car express trains to stop at this station. Previously, the station could only hold six-car local trains. The platform extensions were opened in stages. On April 6, 1948, the platform extension opened for stations from 103rd Street to Dyckman Street, with the exception of 125th Street.
Station layout
This station, located atop an embankment, has two side platforms, two tracks and maintains a level grade. It lies at the northern portal of the Washington Heights Mine Tunnel, which takes the IRT Broadway–Seventh Avenue Line through the bedrock of Manhattan. North of the station, the terrain of Upper Manhattan drops abruptly and the line becomes elevated to Van Cortlandt Park–242nd Street. Both platforms have beige windscreens and red canopies with green frames at the center. A waist-level black fence runs along either side. The platforms are offset as the South Ferry-bound one inclines more to the north than the 242nd Street-bound one. Each platform has two "DYCKMAN ST" mosaics. This is one of only two aboveground Broadway–Seventh Avenue Line stations with two tracks. A center express track, which is currently unused in revenue service, forms just north of this station and runs nonstop to just south of 242nd Street. A spur track used to be located to the south of the station, but was removed when the platforms were extended. The station is listed on the National Register of Historic Places, as is the nearby Substation 17. A 1991 artwork in the waiting area is called Flight by Wopo Holup. It features ceramic relief tiles depicting birds in flight.
Exit
The station's only entrance is a station house slightly above ground level at the southern corner of Nagle Avenue, Dyckman Street, and Hillside Avenue. There is a ramp and stairs from street level to the station house. It has a turnstile bank, token booth, and two staircases to each platform, with an elevator to the southbound platform.
Handicapped access
In February 2014, as part of an ongoing rehabilitation, the MTA built a ramp from street level to the mezzanine and opened an elevator to connect the southbound platform to the mezzanine. The elevator, which was not originally planned in the station renovation, was built due to a lawsuit by the United Spinal Association. The elevator is of a "machine room-less" design and is the first of its type to be installed in the New York City Subway system. The renovations also included rehabilitation of the tunnel portal, realignment and rehabilitation of the platforms and installation of new cast iron lighting fixtures. The southbound elevator is located at the southwest corner of Hillside Avenue, St. Nicholas Avenue, and Fort George Hill, and is accessible by a ramp to the station house. This station is not accessible to the disabled on the northbound side because the suit was settled only after the northbound side was already renovated, and in any case, the area's geography made it prohibitively expensive to add an elevator to the northbound platform. Northbound accessibility was proposed in February 2019 as part of the MTA's "Fast Forward" program.
