IRT Lenox Avenue Line
|IRT Lenox Avenue Line|
|System||New York City Subway|
|Termini||Harlem – 148th Street
Central Park North – 110th Street
|Owner||City of New York|
|Operator(s)||New York City Transit Authority|
|Character||Underground (Except for Harlem – 148th Street)
At-grade (Harlem – 148th Street)
|No. of tracks||2-3|
|Track gauge||4 ft 8 1⁄2 in (1,435 mm)|
|Electrification||600V DC third rail|
|IRT Lenox Avenue Line|
Extent and service
The following services use part or all of the Lenox Avenue Line:
|Time period||Section of line|
|2||all times||south of 145th Street|
|3||all times||full line|
The Lenox Avenue Line begins at the Harlem – 148th Street (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 (with an at-grade crossing between the northbound Lenox track and the southbound White Plains track), 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 and west under Central Park (one of three lines to do so, the other two being the IND 63rd Street Line and the BMT 63rd Street Line), and heads west under 104th Street. The line 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.
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 (known as the West Farms Branch or the West Farms Extension) just after midnight on July 10, 1905. Soon after the line opened, it was speculated that it would bring prosperity to Harlem.
The line has always carried trains of two service patterns, currently designated 2 and 3; see those articles for details. Prior to the 1950s, 1 locals used this line switching to the local at 96th Street.
From March to October 1998, the tunnel that carried the 2 and 3 services had very limited service, and was reconstructed along with the cracked invert (tunnel floor) repaired, correcting a major water problem that existed in this area for many years due to many underground streams located around the Lenox Avenue area that caused extensive water damage, and water seepage problems, causing extensive, severe, and many delays due to constant track and roadbed flooding. Many 2 trains were rerouted via the IRT Lexington Avenue Line, while the 3 trains were rerouted to the 137th Street on the IRT Broadway – Seventh Avenue Line. Supplemental shuttle bus service connecting to other lines in the area were provided at 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.
The entire line is approximately in Harlem.
|Station service legend|
|Stops all times|
|Time period details|
|Harlem – 148th Street||3||May 13, 1968||Formerly 148th Street–Lenox Terminal|
|connecting track to Lenox Yard|
|145th Street||3||November 23, 1904||Only first 5 cars platform
No northbound entrance
|Merge from IRT White Plains Road Line (2 )|
|135th Street||2 3||November 23, 1904|
|125th Street||2 3||November 23, 1904||M60 Select Bus Service to LaGuardia Airport|
|116th Street||2 3||November 23, 1904|
|Central Park North – 110th Street||2 3||November 23, 1904|
|Tracks continue as the IRT Broadway – Seventh Avenue Line express tracks (2 3 )|
- MTA. "Average weekday subway ridership". Retrieved 2 April 2014.
- "East Side Subway Open". The New York Times. November 23, 1904. p. 1. Retrieved October 4, 2011.
- "Subway Trains Running from Bronx to Battery". The New York Times. July 10, 1905. p. 1. Retrieved October 4, 2011.
- "IRT Passengers Get New 148th St. Station". The New York Times. May 14, 1968. p. 95. Retrieved October 4, 2011.
- "Repairs to Lenox Ave. Tunnel To Affect Many Subway Lines". The New York Times. December 12, 1997. Retrieved July 31, 2013.
- Lenox Avenue Rehabilitation Brochure
- "Service Enhancements on 3 Line" (Press release). MTA New York City Transit. 2008-07-24. Retrieved 2008-07-26.
- nycsubway.org — nycsubway.org - IRT Lenox/White Plains Line