As part of Contract 4 of the Dual Contracts, between the city and the BRT, a three-track elevated railway was built above the surface Culver Line from the Fifth Avenue Elevated southeast and south to Coney Island. The Culver Line was operated as a branch of the Fifth Avenue Elevated, with a free transfer at Ninth Avenue to the West End Line into the Fourth Avenue Subway. Avenue X station opened as the line was extended from Kings Highway at noon on May 10, 1919. On October 30, 1954, this station began being served by INDConcourse Express trains operating to Coney Island–Stillwell Avenue as the connection between the IND South Brooklyn Line at Church Avenue and the BMT Culver Line at Ditmas Avenue opened. BMT Culver Line trains were truncated to Ditmas Avenue, the south end of the connection, operating through to Manhattan via the Nassau Street Loopduring the day, and terminating at Ninth Avenue at other times. This Culver Shuttle became full-time on May 28, 1959, and was discontinued in 1975. From June 7, 2016 to May 8, 2017, the Coney Island-bound platform of this station was closed for renovations as part of a $140 million renewal project on the Culver Line. The Manhattan-bound platform was closed for a longer period of time, from May 22, 2017 until July 30, 2018.
Station layout
This station has two side platforms and three tracks with the middle track unused in revenue service. The two platforms have beige windscreens and green canopies that run for nearly the entire length. The north end has black waist-level fences only. The platform signs consist of black boards with "Avenue U" in white lettering.
Exits
This station has two entrances with the full-time one at the north end. From each platform, one staircase leads down to an elevated station-house beneath the tracks, where a bank of turnstiles and token booth are present. Outside fare control are two street stairs to the two northern corners Avenue U and McDonald Avenue. At the south end of the station are unstaffed exits leading to Gravesend Neck Road. From each platform, a single staircase goes down to a short wooden landing outside of a sealed station house where a full-height turnstile and emergency gate provide exit from the system. Another staircase then goes down to the street. The Coney Island-bound side is exit-only while the Manhattan-bound side is HEET turnstile access. The station house, now used as an employee-only facility, was once opened to the public and had a booth.
