page_title: Triborough Bridge
section_title: East River suspension bridge (I-278)
hierarchical_section_title: Triborough Bridge / Description / East River suspension bridge (I-278)
caption_attribution_description: English: Harlem River Lift Bridge, component of the Robert F. Kennedy Bridge from a Circle Line boat approaching from the south on a chilly, cloudy early afternoon
context_page_description: The Triborough Bridge is a complex of bridges and elevated expressway viaducts in New York City. The bridges link the boroughs of Manhattan, Queens, and the Bronx. The viaducts cross Randalls and Wards Islands, which were previously two islands but are now joined by landfill.
  The Triborough Bridge, a toll bridge, carries Interstate 278 as well as the unsigned highway New York State Route 900G. It connects with the FDR Drive and the Harlem River Drive in Manhattan, the Bruckner Expressway and the Major Deegan Expressway in the Bronx, and the Grand Central Parkway and Astoria Boulevard in Queens.
  The three primary bridges of the Triborough Bridge complex are:
  The vertical-lift bridge over Harlem River, the largest in the world, connecting Manhattan to Randalls Island
  The truss bridge over Bronx Kill, connecting Randalls Island to the Bronx
  The suspension bridge over Hell Gate, connecting Wards Island to Astoria in Queens
  These three bridges are connected by an elevated highway viaduct across Randalls and Wards Islands and 14 miles of support roads. The viaduct includes a smaller span across the former site of Little Hell Gate, which separated Randalls and Wards Islands.
context_section_description: The East River span, a suspension bridge across the Hell Gate of the East River, connects Queens with Wards Island. It carries eight lanes of Interstate 278, four in each direction, as well as a sidewalk on the northeastern side. The span connects to Grand Central Parkway, and indirectly to the Brooklyn–Queens Expressway (I-278), in Astoria, Queens. Originally it connected to the intersection of 25th Avenue and 31st Street; the former was later renamed Hoyt Avenue. The suspension span was designed by chief engineer Othmar Ammann. The span was originally designed to be double-decked, with eight lanes on each deck. When the construction of the Triborough Bridge was paused in 1932 due to lack of funding, the suspension span was downsized to a single deck. There are Warren trusses on each side of the span, which stiffen the deck.
  The center span between the two suspension towers is 1,380 feet (421 m) long, and the side spans between the suspension towers and the anchorages are each 700 feet (213 m) long. The total length of the bridge is 2,780 feet (847 m), and the deck is 98 feet (30 m) wide.
  At mean high water, the towers are 315 feet (96 m) tall, and there is 143 feet (44 m) of clearance under the middle of the main span. The suspension towers were originally designed by Arthur I. Perry. Each tower was supposed to have two ornate arches at the top, similar to the Brooklyn Bridge, and was to have been supported by four legs: two on the outside and two in the center. A 1932 article described that each tower would be made of 5,000 tons of material, including 3,680 tons of steel. The final design of the suspension towers, by Ammann, consists of comparatively simple cross bracing supported by two legs.  The tops of each tower contain cast iron saddles in the Art Deco style, over which the bridge's main cables run. These are topped by 30-foot (9.1 m) decorative lanterns with red aircraft warning lights.
  The span is supported by two main cables, which suspend the deck and are held up by the suspension towers. Each cable is 20 inches (51 cm) in diameter and contains 10,800 miles (17,400 km) of individual wires. At the Wards Island and Astoria ends of the suspension span, there are two anchorages that hold the main cables. The anchorages contain a combined 133,500 tons of concrete.
caption: The Harlem River lift bridge in 2007