The Lenox Avenue Line begins at the Harlem–148th Street station, which was formerly known as 148th Street–Lenox Terminal. After the terminal, a track merges from the Lenox Yard, and the line heads south under Lenox Avenue. At 142nd Street Junction, the IRT White Plains Road Line merges, carrying through service from the Bronx. At the north border of Central Park is the final stop on the line, Central Park North–110th Street. From there the line curves southwest under the North Woods and North Meadow of Central Park, being one of three lines to pass under the park. It heads west under 104th Street, then turns southwest and south to run underneath the IRT Broadway–Seventh Avenue Line, passing under part of the northbound platform at 103rd Street. After the center express track on the Broadway–Seventh Avenue Line ends by connecting to the two local tracks, the Lenox Avenue Line rises to become the two express tracks, with double crossovers to each local direction. The four-track Broadway–Seventh Avenue line then continues south through 96th Street, an express station and transfer point.
History
The line opened south of 145th Street just after midnight on November 23, 1904, as part of the IRT's original system. It was known as the East Side Subway or East Side Branch at the time, as it was the spur of the main line to the east side. The first train ran from the line onto the IRT White Plains Road Line just after midnight on July 10, 1905. Soon after the line opened, it was speculated that it would bring prosperity to Harlem. The line ran across the path of the Harlem Creek, a creek that had once been located above ground but had been buried by the first decade of the 20th century. The creek's presence caused flooding in the line's early years, especially around 116th Street. In April 1907, IRT officials decided to create a concrete drain beneath the Lenox Avenue Line tunnel, during which time trains in both directions ran on the southbound track during late nights. The line has always carried trains of two service patterns, currently designated and. Prior to February 6, 1959, 3 trains switched to the local on the IRT Broadway–Seventh Avenue Line north of 96th Street. Afterwards, all trains running from the Lenox Avenue Line ran express. Originally the line north of the 142nd Street Junction was only intended to be a yard lead to Lenox Yard, and sometime afterwards it was suggested to add a station at 145th Street. The Harlem–148th Street station was opened on May 13, 1968 on land that had been part of the Lenox Yard; the station was originally called Lenox Terminal–148th Street. Starting on March 2, 1998, the tunnel was reconstructed along with the cracked invert. This was done to correct a major water problem that had existed for many years due to the continued presence of the Harlem Creek and other underground streams, which caused extensive flooding, water damage, and seepage problems that occasionally contributed to severe service disruptions. The project cost $82 million and was finished on October 12, 1998. During the reconstruction, many trains were rerouted via the IRT Lexington Avenue Line, while the trains were rerouted to the 137th Street–City College station on the IRT Broadway–Seventh Avenue Line. Each of the two Lenox Avenue Line tracks were alternately taken out of service, the 116th Street station was closed, and supplemental shuttle bus service connecting to other lines in the area were provided for much of this time. From 1995 until 2008, the line's two northernmost stations, Harlem–148th Street and 145th Street, were served by shuttle buses during the late-night hours. Full-time service was restored on July 27, 2008. On March 27, 2020, a northbound 2 train caught fire while approaching Central Park North–110th Street, the southernmost station on the line. The fire killed the train's motorman and injured 16. Subway service on the Lenox Avenue Line resumed on March 30, bypassing the Central Park North station until it reopened on April 6.
