The Interborough Rapid Transit Company (IRT) was the private operator of the original underground New York City Subway line that opened in 1904, as well as earlier elevated railways and additional rapid transit lines in New York City. The IRT was purchased by the City in June 1940. The former IRT lines (the numbered routes in the current subway system) are now the A Division or IRT Division of the Subway.
The first IRT subway ran between City Hall and 145th Street at Broadway, opening on October 27, 1904. It opened following more than twenty years of public debate on the merits of subways versus the existing elevated rail system and on various proposed routes.
Founded on May 6, 1902, by August Belmont, Jr., the IRT's mission was to operate New York City's initial underground rapid transit system after Belmont's and John B. McDonald's Rapid Transit Construction Company was awarded the rights to build the railway line in 1900, outbidding Andrew Onderdonk. On April 1, 1903, over a year before its first subway line opened, the IRT acquired the pre-existing elevated Manhattan Railway by lease, gaining a monopoly on rapid transit in Manhattan. The Manhattan EL was the operator of four elevated railways in Manhattan with an extension into the Bronx. The IRT coordinated some services between what became its subway and elevated divisions, but all the lines of the former Manhattan EL have since been dismantled.
In 1913, as a result of massive expansion in the city, the IRT signed the Dual Contracts with Brooklyn Rapid Transit (BRT) in order to expand the subway.
In 1932, with the introduction of IND trains, all IRT lines began to get "coded" with numbers, with single digits representing subway lines, and double digits representing el lines:
- 1 operated between 137 St and South Ferry via 7 Av local; rush hours and late nights to Dyckman St and 242 Street respectively.
- 2 ran between 241 Street and Flatbush Av.
- 3 ran between 145 Street and New Lots.
- 4 ran between Woodlawn and Utica Av. Nights and weekends end at South Ferry.
- 5 ran between 180 St and South Ferry weekdays, with special rush hour service between 241 St and Utica Av
- 6 ran between Pelham Bay and City Hall.
- 7 and 8 ran between Times Square and Flushing. 7 was the local variant while 8 was express.
- 9 ran between 242 St and Flatbush Av, no late night service.
- 10 ran between 129 St and City Hall making all stops.
- 11 ran between Ditmars Blvd and South Ferry making all stops.
- 12 ran between Bronx Park terminal and City Hall, running express in Manhattan. Late nights all stops.
- 13 ran between 129 St and City Hall making all stops.
- 14 ran between 241 St and City Hall, operating express south of Tremont Av. Nights operates as a shuttle between Fordham and 241 St.
- 15 ran between 180 St and City Hall, running express in Manhattan weekdays.
- 16 ran between 155th St and South Ferry, making all stops.
- 17 ran between Burnside Av and South Ferry, running express in Manhattan.
- 18 ran between 155th St and South Ferry, making all stops.
- 19 ran between Burnside Av and South Ferry, running express in Manhattan.
Most lines were named after their Manhattan lines. This includes 1, 2, 3, 9 for 7 Av, 4, 5, 6 for Lex Av, 7, 8 for 42 St, 10, 11, 12 for 2 Av, 13, 14, 15 for 3 Av, 16, 17 for 6 Av, and 18, 19 for 9 Av.
The IRT ceased to function as a privately held company on June 12, 1940, when its properties and operations were acquired by the City of New York. Many Els were torn down between 1938 and 1940. This caused the elimination of the 16 and 17 (19 extended to Burnside to replace service lost at the time), and then the 10, 12, 18, and 19 were discontinued. By this time, 8 service was rerouted onto Second Av to South Ferry making all express stops and 13 extended into the Bronx to the Bronx Park terminal. 14 trains extended to South Ferry for 2 Av replacement.
El dismantling began again between 1949 and 1955. The remainder of the 2 Av el was shut down with an extension of the BMT lines into Queens. First, 8 and 11 service was discontinued and the 7 operated some express trains similar to original 8 service. Then in 1950, all service to South Ferry ended, running 13-15 trains to either Chatham Sq or City Hall.
In 1951, 13 service ended operation, expanding 15 service and running it local in Manhattan. 14 service was local in the Bronx. By the end of 1953, all trains ended at Chatham Sq.
In 1955, the remainder of the 3 Av el south of 149 St was abandoned and ended both 14 and 15 service. The remainder of the 3 Av el ran between 149 St and Gun Hill Rd and simply ran without a number name. It was most commonly called the 3 Av line. By 1973, the el extended to the IRT Pelham Line at 138th st and was renamed 8.
Today, the remaining lines are operated as the A Division of the subway. The lines are underground in Manhattan, except for a short stretch across Harlem at 125th Street and in northernmost Manhattan. Its many lines in the Bronx are predominantly elevated, with some subway, and some railroad-style right-of-way acquired from the defunct New York, Westchester and Boston Railway, which now constitutes the IRT Dyre Avenue Line. Its Brooklyn lines are underground with a single elevated extension that reaches up to New Lots Avenue, and the other reaching Flatbush Avenue via the underground Nostrand Avenue Line. The Flushing Line, its sole line in Queens, is entirely elevated except for a short portion approaching its East River tunnel and its terminal at Flushing–Main Street (the whole Manhattan portion of the line is underground). The Flushing Line has had no track connection to the rest of the IRT since 1949, when service on the Second Avenue El was discontinued, although at that time is wasconnected to the BMT and the rest of the system via the BMT Astoria Line on the upper level of the Queensboro Plaza station.
The Bronx and ManhattanEdit
Trunk lines include:
- Lexington Avenue Line (4, 5, 6, 8), under Park and Lexington Avenues, as well as under Lafayette Street and Broadway
- Broadway–Seventh Avenue Line (1, 2, 3, 9), under and over Broadway, as well as under Seventh Avenue, Varick Street, and West Broadway
- Flushing Line (7), under 41st and 42nd Streets
- 42nd Street Shuttle, under 42nd Street
Branch lines include:
- Lenox Avenue Line (2, 3), under Lenox Avenue and Central Park
- White Plains Road Line (2, 5), under East 149th Street, and over Westchester Avenue, Southern Boulevard, Boston Road, and White Plains Road
- Pelham Line (6), under East 138th Street and Southern Boulevard, and over Westchester Avenue
- Jerome Avenue Line (4), under Grand Concourse, over River and Jerome Avenues,
- Third Avenue Line (8) under Brook Avenue, and over Third Avenue and Webster Avenue.
Brooklyn and QueensEdit
There were three Brooklyn lines built by the IRT:
- Eastern Parkway Line (2, 3, 4, 5), under Fulton Street, Flatbush Avenue, and Eastern Parkway
- New Lots Line (3, 4), over East 98th Street and Livonia Avenue
- Nostrand Avenue Line (2, 5), under Nostrand Avenue
The only line in Queens is the Flushing Line (7), under 50th Avenue, and over Queens Boulevard and Roosevelt Avenue.
(of the East and Harlem Rivers, from south to north) [Joralemon Street Tunnel (4, 5)
- Clark Street Tunnel (2, 3)
- Steinway Tunnel (7)
- Lexington Avenue Tunnel (4, 5, 6, 8)
- 149th Street Tunnel (2)
- Broadway Bridge (1, 9)
- Dyre Avenue Line (5), parallel to the Esplanade, and on the old right-of-way of the New York, Westchester and Boston Railway in 1941
- Second Avenue Line (8, 11), on October 16, 1949, the Line ended. The Astoria Line had its platforms shaved back for exclusive BMT operation.
- Lenox Avenue Line to Harlem – 148th Street (3), at-grade parallel to 149th Street in 1968
- Third Avenue Line rebuild from 163rd Street to 138th Street (8), new el over Brook Avenue between 163rd Street and 149th St, then subway under Brook Avenue from 149th Street to 138th Street on the 6. The el west of Brook Avenue dismantled in the 1980s.
- Broadway–Seventh Avenue Line to new South Ferry island-platformed stations (1, 9), opened March 16, 2009 and closed temporarily on October 28, 2012 because of Hurricane Sandy.
- Flushing Line to 34th Street–Hudson Yards (7), under 41st Street and 11th Avenue, opened September 13, 2015