Early history of the IRT subway in the context of "Interborough Rapid Transit Company"

The New York City Subway is a rapid transit system that serves four of the five boroughs of New York City, New York: the Bronx, Brooklyn, Manhattan, and Queens. Its operator is the New York City Transit Authority, which is itself controlled by the Metropolitan Transportation Authority of New York. In 2015, an average of 5.65 million passengers used the system daily, making it the busiest rapid transit system in the United States and the 11th busiest in the world.

The present New York City Subway system is composed of three formerly separate systems that merged in 1940: the Interborough Rapid Transit Company (IRT), the Brooklyn–Manhattan Transit Corporation (BMT), and the Independent Subway System (IND). The privately held IRT, founded in 1902, constructed and operated the first underground railway line in New York City. The opening of the first line on October 27, 1904, is commonly cited as the opening of the modern New York City Subway, although some elevated lines of the IRT and BMT that were initially incorporated into the New York City Subway system but then demolished predate this. The oldest sections of elevated lines still in operation were built in 1885. The BMT, founded in 1923 and also privately held, was formed from the bankruptcy of the Brooklyn Rapid Transit Company. The IND was created by the City of New York in 1921 to be a municipally owned competitor of the two private companies. Unification in June 1940 by the New York City Board of Transportation brought the three systems under one operator. The New York City Transit Authority, created in 1953 to be a public benefit corporation that acquired the rapid transit and surface line (buses and streetcars) infrastructure of the Board of Transportation, remains the operator of the New York City Subway today.

The Times Square–42nd Street station is a major New York City Subway station complex located under Times Square, at the intersection of 42nd Street, Seventh Avenue, and Broadway, in Midtown Manhattan. The complex allows free transfers between the IRT 42nd Street Shuttle, the BMT Broadway Line, the IRT Broadway–Seventh Avenue Line and the IRT Flushing Line, as well as to the IND Eighth Avenue Line a block west at 42nd Street–Port Authority Bus Terminal. The complex is served by the 1, 2, 3, 7, N and Q trains at all times, the W train during weekdays; the R and 42nd Street Shuttle (S) trains at all times except late nights; and <7> trains during rush hours in the peak direction. A free passageway from the shuttle platform to the 42nd Street–Bryant Park/Fifth Avenue station, served by the 7, <7>​​, B, ​D, ​F, <F>, and ​M trains, is open during the day from 6 a.m. to 12 a.m.

The present shuttle platforms were built for the Interborough Rapid Transit Company (IRT) as a local station on the city's first subway line, which was approved in 1900. The station opened on October 27, 1904, as one of the original 28 stations of the New York City Subway. As part of the Dual Contracts between the IRT and the Brooklyn–Manhattan Transit Corporation (BMT), the Broadway–Seventh Avenue Line platforms opened in 1917, followed by the Broadway Line platforms in 1918 and the Flushing Line platforms in 1928. The original platforms were also reconfigured to serve the shuttle. The complex has been reconstructed numerous times over the years. The free transfer between the IRT and BMT opened in 1948, while the transfer to the IND station was placed within fare control in 1988. The complex was placed on the National Register of Historic Places in 2004. In the early 21st century, the shuttle station was reconfigured.

The IRT Lexington Avenue Line (also known as the IRT East Side Line and the IRT Lexington–Fourth Avenue Line) is one of the lines of the A Division of the New York City Subway, stretching from Lower Manhattan north to 125th Street in East Harlem. The line is served by the 4, ​5, ​6, and <6> trains.

The line was constructed in two main portions by the Interborough Rapid Transit Company (IRT), a private operator. The first portion, from City Hall north to 42nd Street, was opened between 1904 and 1908, and is part of the first subway line in the city. The original subway turned west across 42nd Street at the Grand Central station, then went north at Broadway, serving the present-day IRT Broadway–Seventh Avenue Line. The second portion of the line, north of 42nd Street, was constructed as part of the Dual Contracts, which were signed between the IRT; the Brooklyn Rapid Transit Company, via a subsidiary; and the City of New York.

The Broadway Bridge is a vertical-lift bridge across the Harlem River Ship Canal in the borough of Manhattan in New York City. It connects the neighborhoods of Inwood on Manhattan Island and Marble Hill on the mainland. The bridge consists of two decks. The lower deck carries Broadway, which is designated as U.S. Route 9 at this location. The upper deck carries the New York City Subway's IRT Broadway–Seventh Avenue Line, serving the 1 train.

The site was previously occupied by two successive swing bridges. The first, known as the Harlem Ship Canal Bridge, was built between 1893 and 1895 to cross the canal, which had been constructed to bypass a meandering alignment of the Spuyten Duyvil Creek. By the first decade of the 20th century, the construction of the city's first subway line had made the original bridge obsolete, and a double-decker span called the 225th Street Bridge was built to accommodate the subway line above highway traffic. Between 1905 and 1906, the second bridge was installed, and the first bridge was relocated southward on the Harlem River, becoming the University Heights Bridge.

The 125th Street station (formerly the Manhattan Street station) is an elevated local station on the IRT Broadway–Seventh Avenue Line of the New York City Subway. Located at the intersection of 125th Street and Broadway, at the border of the Manhattanville and Morningside Heights neighborhoods of Manhattan, it is served by the 1 train at all times.

The 125th Street station was constructed for the Interborough Rapid Transit Company (IRT) as part of the city's first subway line, which was approved in 1900. Construction of the line segment that includes 125th Street began on June 18 of the same year. The station opened on October 27, 1904, as one of the original 28 stations of the New York City Subway. The station's platforms were lengthened in 1948, and the station was renovated in the 2000s.