[6] 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.

For New York City's transportation system, the project was "a more important engineering feat than the building of the Panama Canal" according to the IRT.

In 1943, Sunday evening local trains were rerouted to City Hall, with shuttles from Canal Street running to South Ferry.

On November 5, 1946, service to Freeman Street was stopped, and all weekday and Saturday morning peak locals were routed to South Ferry.

On April 30, 1950, all Sunday locals were routed to South Ferry, with a shuttle connection from Canal Street to City Hall.

[15] However, this resulted in severe overcrowding, so local service to Fordham Road in the PM peak direction was resumed on December 3, 1952.

Local-expresses and thru-expresses operated between Gun Hill Road and Chatham Square southbound in the AM and northbound in the PM peak hours.

The committee initially sought a decrease in train service, saying the noise from the elevated "constitutes a menace to health, comfort and peaceable home life.

[16] On May 12, 1955, the main portion of the line closed from Chatham Square to East 149th Street in the Bronx, ending the operation of elevated service in Manhattan.

[21][22][23] The removal was a catalyst in a wave of new construction, adding property values on the East Side, while bringing increased isolation and hastened decline throughout much of the Bronx.

[24] The head of the Real Estate Board of New York suggested that Third Avenue be renamed "the Bouwerie" to symbolize the transformation.

[29] Local residents and business owners also sought similar revival seen following the closure of the line's sections in Manhattan.

[31] The remaining portion in the Bronx from East 149th Street to Gun Hill Road finally closed on April 29, 1973[32][33] and demolition started on March 9, 1977.

With the introduction of free bus to subway transfers systemwide in the 1990s, the three routes lost their special status, although the B42 terminates in a loop inside fare control at Rockaway Parkway.

It was partially replaced by the Bx41 SBS and the Bx15 Limited, which runs to West Harlem via 125th Street, but does not extend past Fordham Plaza to Gun Hill Road.