The Three Sisters are three similar self-anchored suspension bridges spanning the Allegheny River in downtown Pittsburgh, Pennsylvania at 6th, 7th, and 9th streets, generally running north–south. The bridges have been given formal names to honor important Pittsburgh residents:
The Roberto Clemente Bridge, also known as the Sixth Street Bridge, spans the Allegheny River in downtown Pittsburgh, Pennsylvania, United States.
The Smithfield Street Bridge is a lenticular truss bridge crossing the Monongahela River in Pittsburgh, Pennsylvania, USA.
The Coraopolis Bridge[1] is a girder bridge over the back channel of the Ohio River connecting Grand Avenue on Neville Island to Ferree Street in Coraopolis, Pennsylvania. It opened in 1995 to replace a structure of historic significance. The original Pratt/Bowstring/Pennsylvania[2] through truss spans, designed by Theodore Cooper, were formerly the (third) Sixth Street Bridge, spanning the Allegheny River, in downtown Pittsburgh, and were built in 1892 by the Union Bridge Company. They were floated downstream by the Foundation Company in 1927 rather than being demolished when the bridge was removed to enable construction of the present (fourth) Three Sisters (Pittsburgh) Sixth Street Self-anchored suspension bridge. However, by the late 1980s, the old bridge could no longer support traffic volumes and was replaced by a newer structure.
The Hot Metal Bridge is a truss bridge in Pittsburgh, Pennsylvania, that crosses the Monongahela River. The bridge consists of two parallel spans on a single set of piers: the former Monongahela Connecting Railroad Bridge, built in 1887, on the upstream side and the former Hot Metal Bridge, built in 1900, on the downstream side. The Monongahela Connecting Railroad Bridge carried conventional railroad traffic, while the Hot Metal Bridge connected parts of the J&L Steel mill, carrying crucibles of molten iron from the blast furnaces in ladle transfer cars to the open hearth furnaces on the opposite bank to be converted to steel. During World War II 15% of America's steel making capacity crossed over the Hot Metal Bridge, up to 180 tons per hour. The upstream span was converted to road use after a $14.6 million restoration, and opened by Mayor Tom Murphy with a ceremony honoring former steel workers on June 23, 2000. The bridge connects 2nd Avenue at the Pittsburgh Technology Center in South Oakland with Hot Metal Street in the South Side. The downstream span reopened for pedestrian and bicycle use in late 2007 after two years of work. The Great Allegheny Passage hiker/biker trail passes over this bridge as it approaches Pittsburgh's Golden Triangle area.
The Fort Wayne Railroad Bridge, listed as the Pennsylvania Railroad Bridge on the National Register of Historic Places, is a double-deck steel truss railroad bridge spanning the Allegheny River in Pittsburgh, Pennsylvania.
The West End Bridge is a steel tied-arch bridge over the Ohio River in Pittsburgh, Pennsylvania, approximately 1 mile (1.6 km) below the confluence of the Allegheny and Monongahela Rivers. It connects the West End to the Chateau neighborhood on the North Side of Pittsburgh.
Wendel Bollman was an American self-taught civil engineer, best known for his iron railway bridges. Only one of his patented "Bollman truss" bridges survives, the Bollman Truss Railroad Bridge in Savage, Maryland. The Wells Creek Bollman Bridge near Meyersdale, Pennsylvania is also standing, although that bridge uses the Warren truss system.
Andy Warhol Bridge, also known as the Seventh Street Bridge, spans the Allegheny River in Downtown Pittsburgh. It is the only bridge in the United States named for a visual artist. It was opened at a cost of $1.5 million on June 17, 1926, in a ceremony attended by 2,000.
The McKees Rocks Bridge is a steel trussed through arch bridge which carries the Blue Belt, Pittsburgh's innermost beltline, across the Ohio River at Brighton Heights and McKees Rocks, Pennsylvania, connecting Pennsylvania Route 65 with Pennsylvania Route 51, west of the city.
The Ohio Connecting Railroad Bridge is a steel bridge which crosses the Ohio River at Brunot's Island at the west end of Pittsburgh, Pennsylvania, United States. It consists of two major through truss spans over the main and back channels of the river, of 508 feet (155 m) and 406 feet (124 m) respectively, with deck truss approaches.
The David McCullough Bridge, commonly and historically known as the 16th Street Bridge, is a steel trussed through arch bridge that spans the Allegheny River in Pittsburgh, Pennsylvania.
The Herr's Island Railroad Bridge, also known as the West Penn Railroad Bridge, is a truss bridge across the Allegheny River in the United States between the Pittsburgh neighborhoods of Troy Hill and Herrs Island.
The Bessemer & Lake Erie Railroad Bridge is a truss bridge that carries the Canadian National Railway's Bessemer and Lake Erie Railroad division across the Allegheny River between the Pittsburgh suburbs of Plum and Harmar Township, Pennsylvania. In 1897, a single-track trestle and viaduct was built on this site; in 1918, the original piers were doubled in width, the current double-tracked structure built alongside, and then slid into place. The original north trestle approach was buried in slag dumped from an adjacent temporary filling trestle.
The Emlenton Bridge is a steel-deck truss bridge that spans the Allegheny River just south of the town of Emlenton, Pennsylvania, United States at approximately mile marker 44.4 on I-80. With a height of 270 feet (82 m) above the river, the Emlenton Bridge was the highest bridge in the Interstate Highway System when completed in 1968. This record was held until 1971 with the opening of the Fred G. Redmon Bridge near Selah, Washington.
Pennsylvania Railroad, Connecting Railway Bridge is a stone arch bridge in Philadelphia, Pennsylvania, that carries Amtrak Northeast Corridor rail lines and SEPTA and NJT commuter rail lines over the Schuylkill River. It is located in Fairmount Park, just upstream from the Girard Avenue Bridge.
The Oil City Pennsylvania Railroad Bridge is an American out of service truss bridge that carries the Western New York and Pennsylvania Railroad (WNY&P) across the Allegheny River between Cranberry Township and Oil City, Pennsylvania.
The Inclined Plane Bridge is a 237-foot (72 m), Pennsylvania through truss bridge that spans Stonycreek River in Johnstown, Cambria County, in the U.S. state of Pennsylvania. It connects the city to the lower station of the Johnstown Inclined Plane. The bridge was listed on the National Register of Historic Places in 1988 and was documented by the Historic American Engineering Record (HAER) in 1997.
The Manchester Bridge, also known as the North Side Point Bridge, was a steel Pratt truss bridge that spanned the Allegheny River in Pittsburgh, Pennsylvania.
The Point Bridge was a steel cantilever truss bridge that spanned the Monongahela River in Pittsburgh, Pennsylvania.
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