Third Avenue Bridge New York carries southbound road traffic on Third Avenue over the Harlem River, connecting the boroughs of Manhattan and the Bronx in New York City. It once carried southbound New York State Route 1A. The Third Avenue Bridge carries traffic south from Third Avenue, East 135th Street, Bruckner Boulevard, and Lincoln Avenue in the Bronx, to East 128th Street, East 129th Street, Lexington Avenue, and the Harlem River Drive in Manhattan, traveling over the Metro-North Railroad Oak Point Link, the Harlem River, and Harlem River Drive. The bridge was formerly bidirectional, but converted to one-way operation southbound on August 5, 1941 on the same day the Willis Avenue Bridge was similarly converted to one-way northbound.
As part of a major reconstruction project, a new swing span was floated into place on October 29, 2004 and two lanes of Manhattan-bound traffic opened on December 6, 2004. Additional work covered redesign of the approach ramps to the bridge on the Bronx side and off the bridge in Manhattan. Discovery Channel made a television show about the installation. As reconstructed, the Third Avenue Bridge carries five lanes of Manhattan-bound traffic from the Bronx, which split to three ramps in Manhattan: to East 128th Street and Second Avenue; to Lexington Avenue and East 129th Street; and to the southbound Harlem River Drive/FDR Drive.