Dunlap's Creek Bridge | |
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Carries | National Road |
Crosses | Dunlap's Creek |
Locale | Brownsville, Pennsylvania |
Designer | Richard Delafield |
Design | arch bridge |
Material | cast iron |
Longest span | 24.4 metres (80 ft)[1] |
Number of spans | 1 |
Construction begin | 1836 |
Construction end | 1839 |
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Dunlap's Creek Bridge
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Governing body: | State |
NRHP Reference#: | 78002398[3] |
Added to NRHP: | July 31, 1978 |
Dunlap's Creek Bridge was the first cast iron, metal arch bridge in the United States. It was designed by Richard Delafield and built by the United States Army Corps of Engineers.[4] Constructed from 1836 to 1839 on the National Road in Brownsville, Pennsylvania, it remains in use today. It is listed on the National Register of Historic Places and is a National Historic Civil Engineering Landmark (1978).
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There have been four structures on this site. The first two collapsed in 1808 and 1820. The third, a wood frame structure, needed replacement by 1832.[5]
This bridge is constructed using five parallel tubular ribs, each made of 9 elliptical segments to form the 80 feet (24 m) arch.[4]