Suburban Rapid Transit Company

The IRT Third Avenue Line, commonly known as the Third Avenue El and the Bronx El, was an elevated railway in Manhattan and the Bronx, New York City. Originally operated by the New York Elevated Railway, an independent railway company, it was acquired by the Interborough Rapid Transit Company (IRT) and eventually became part of the New York City subway system.

The first segment of the line, with service at most stations, opened from South Ferry to Grand Central Depot on August 26, 1878. Service was extended to Harlem in Manhattan on December 30. Service in Manhattan was phased out in the early 1950s and closed completely on May 12, 1955, and ended in the Bronx on April 29, 1973.

The Third Avenue El was the last elevated line to operate in Manhattan, other than the 1 train on the IRT Broadway–Seventh Avenue Line (which has elevated sections between 122nd and 135th Streets and north of Dyckman Street), and was a frequent backdrop for movies. Service on the Second, Sixth and Ninth Avenue El lines was terminated in 1942, 1938, and 1940, respectively.

In 1875, the Rapid Transit Commission granted the New York Elevated Railway Company the right to construct the railway from Battery Park to the Harlem River along the Bowery and Third Avenue. At that time the company already operated the Ninth Avenue Elevated, which it acquired in 1871 after the bankruptcy of the West Side and Yonkers Patent Railway. The Third Avenue El opened in 1878, running from South Ferry to 129th Street. The Manhattan Railway Company took control of the New York Elevated Railroad in 1879. In 1886, the Suburban Rapid Transit Company commenced operations with a railway line over the Harlem River (via a double-decked swing bridge located between the Third Avenue Bridge and Willis Avenue Bridge with the upper deck carrying the express tracks, the lower one the local tracks, and a pedestrian walkway) from the Manhattan Railway's northern terminal at 129th Street to 133rd Street in the southern Bronx, known then as the "Annexed District". The Manhattan Railway assumed operations of the Suburban in 1891 as an extension of the Third Avenue Line, and through service between the Bronx and Manhattan began in 1896. A 999-year lease of the Manhattan Railway was brokered by the Interborough Rapid Transit Company in 1902, for which rapid transit services in the Bronx, of which the Third Avenue Line was a part, would eventually be coordinated alongside the new subway. Around this time, the line was electrified.

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