[7] The southern tube rises to ground level east of Second Avenue, where it is fed by eastbound traffic on 36th Street, as well as by entrance ramps from the north and south.

[9] The Manhattan side was originally also supposed to link with the proposed Mid-Manhattan Expressway and the East River (FDR) Drive, though neither connection was built.

[23][24] The tower on the Manhattan side is an octagon-shaped structure located on a city-owned block bounded by 41st and 42nd Streets, First Avenue, and the FDR Drive.

[25][26] The Queens side's ventilation building is a rectangular tower located in the center of Borden Avenue between Second and Fifth Streets.

At the time, there was frequent and heavy congestion on bridges across the East River, which separated Manhattan from the boroughs of Queens and Brooklyn on Long Island.

[35][36] That December, Mayor James J. Walker formed a commission to study traffic congestion on New York City bridges and tunnels.

[35] Local civic groups felt that it would be inadequate to simply increase capacity on existing crossings like the Queensboro Bridge, since there were no roads connecting Long Island with Midtown Manhattan.

[39] The groups stated that the tunnel would act as a relief corridor for traffic from midtown Manhattan, which at the time had to use other crossings to the north or south.

[45] Simultaneously, civic groups proposed a 4.3-mile (6.9 km)[46] system of tunnels under Manhattan, connecting Queens in the east with Weehawken, New Jersey, in the west.

[42][48] The Fifth Avenue Association further proposed that the city create a bridge-and-tunnel authority to would raise funding and oversee construction and operations.

[51] The study's authors suggested that the city construct a network of parkways and expressways, including a major highway leading from Long Island to the Manhattan-Queens tunnel.

[57] Civic groups convened a special session in which they asked the New York City Board of Estimate to override the laws so the tunnel could be approved.

[61] Around this time, engineers revised the Triborough Tunnel's eastern approaches, moving the route of the Brooklyn spur from 11th to 21st Street.

[66] In December 1930, the United States Department of War approved the construction of the Triborough Tunnel, since the tube would not hinder maritime navigation during wartime.

[75] La Guardia supported the immediate construction of the tunnel because he believed it would help traffic get from Manhattan to the 1939 New York World's Fair in Queens.

[76] The Queens–Midtown Tunnel Authority applied for a federal loan and grant, worth a combined $58.4 million, from the Public Works Administration (PWA) that September.

[78] In response to the RFC's offer, PWA chairman Harold L. Ickes stated that his agency had $32.7 million readily available for the construction of the tunnel.

Moses's agency would be the only entity who could construct and operate a toll bridge entirely within the New York City limits, and the already-approved federal funding for the tunnel would be canceled if the project was delayed too long.

First, the Queens–Midtown Tunnel's path passed through a large concentration of solid rock, although there were also some pockets of dirt under the river that would be easy to dig through.

[115] Eventually, officials agreed to construct the 2.5-mile (4.0 km) link to what is now the Brooklyn-Queens Expressway, forming part of a longer highway that connected directly to LaGuardia Airport.

[125] Workers primarily dug underwater using tunnelling shields that drilled inward from both portals of each tube, but used dynamite to blast through thick sheets of rock.

[110][5] In March 1939, the PWA released a report predicting that the tunnel would not be complete until summer 1941, eight months later than originally planned, due to geological difficulties.

[137] The fans were being installed in the ventilation buildings,[24] and property at the Queens portal was being demolished to make way for the tunnel approaches.

Senator Robert F. Wagner; and New York City Council president Newbold Morris, who was attending in La Guardia's stead.

[177][178] Each spring from 1981 to 2016, the tunnel was closed to traffic for a few hours overnight to accommodate the annual "Ringling Bros. and Barnum & Bailey Circus Animal Walk".

[180] The walk became an annual tradition, and crowds of several hundred people would gather at the Queens–Midtown Tunnel's Queens portal to see the march in the middle of the night.

[186] The $132 million project,[187] completed in May 2001, involved replacing the roof with 930 slabs of concrete that were suspended from brackets glued onto the tunnel shell.

A state judge found that the MTA did not break any laws or ethical obligations when it awarded the contract to the Pataki donor instead of another competitor.

[193] On September 4, 2024, a contractor conducting surveys for the East River Greenway accidentally drilled through the roof of one of the tubes, causing water to leak into the tunnel, and forcing it to be closed for emergency repairs.

[201][202][203] Congestion pricing in New York City was implemented in January 2025;[229] drivers who enter Manhattan via the tunnel pay a second toll.