The 178th and 179th Street Tunnels are two disused vehicular tunnels in Upper Manhattan in New York City. Originally conceived and constructed under the auspices of Robert Moses, the twin tunnels have been superseded by the Trans-Manhattan Expressway in Washington Heights, which itself runs through a cut with high-rise apartments built over it in places. In the 1950s, the Trans-Manhattan Expressway (I-95) was constructed as a high-speed interstate bypass of the tunnels, and by 1962, the two tunnels were out of commission. Both tunnels are now are being used by the Port Authority of New York and New Jersey as storage space. History The tunnels were built to carry traffic between the east side of Upper Manhattan and the George Washington Bridge (which opened in 1931) on the west side. Originally, only the 178th Street Tunnel was built, consisting of a tube with a width of and a clearance of . It carried traffic to and from the George Washington Bridge at the western end. The eastern end split into two directions: a ramp to Amsterdam Avenue on the right and a driveway south to the Harlem River Drive on the left. Plans for the 178th Street Tunnel were approved in 1930, and the tunnel was nearly completed by early 1932. However, the opening of the tube was postponed for several years until traffic growth warranted the tunnel's opening, and the Port Authority resumed construction in 1938 for the 1939 New York World's Fair. After delays related to the construction of the Harlem River Drive ramp, the 178th Street Tunnel opened on June 27, 1940, serving both directions of traffic. Due to labor shortages and low traffic during World War II, the tunnel was closed in May 1942, reopening in November 1945. While the 179th Street Tunnel had been planned along with its counterpart in 1930, engineers waited until the traffic loads demanded the opening of a new tunnel. By the late 1940s, the 178th Street Tunnel was frequently congested. Construction began on the 179th Street Tunnel in June 1949. The work involved constructing the Highbridge Interchange, which contained ramps from the 178th Street Tunnel to the Harlem River Drive, Amsterdam Avenue, and the Washington Bridge across the Harlem River, as well as corresponding ramps from these roads to the 179th Street Tunnel. The ramp from the 178th Street Tunnel to Harlem River Drive, which had been completed only a