__NOTOC__ Dunlap's Creek Bridge is the first

arch bridge An arch bridge is a bridge with abutments at each end shaped as a curved arch. Arch bridges work by transferring the weight of the bridge and its structural load, loads partially into a horizontal thrust restrained by the abutments at either si ...

in the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

built of

cast iron Cast iron is a class of iron–carbon alloys with a carbon content of more than 2% and silicon content around 1–3%. Its usefulness derives from its relatively low melting temperature. The alloying elements determine the form in which its car ...

. It was designed by

Richard Delafield Richard Delafield (September 1, 1798 – November 5, 1873) was a United States Army officer for 52 years. He served as superintendent of the United States Military Academy for a total of 12 years. At the start of the American Civil War, then ...

and built by the

United States Army Corps of Engineers The United States Army Corps of Engineers (USACE) is the military engineering branch of the United States Army. A direct reporting unit (DRU), it has three primary mission areas: Engineer Regiment, military construction, and civil wo ...

. Constructed from 1836 to 1839 on the

National Road The National Road (also known as the Cumberland Road) was the first major improved highway in the United States built by the federal government. Built between 1811 and 1837, the road connected the Potomac and Ohio Rivers and was a main tran ...

Brownsville, Pennsylvania Brownsville is a borough in Fayette County, Pennsylvania, United States, first settled in 1785 as the site of a trading post a few years after the defeat of the Iroquois enabled a resumption of westward migration after the American Revolutionary ...

, it remains in use today. It is listed on the

National Register of Historic Places The National Register of Historic Places (NRHP) is the Federal government of the United States, United States federal government's official United States National Register of Historic Places listings, list of sites, buildings, structures, Hist ...

and is a

National Historic Civil Engineering Landmark __NOTOC__ The following is a list of Historic Civil Engineering Landmarks as designated by the American Society of Civil Engineers since it began the program in 1964. The designation is granted to projects, structures, and sites in the United Stat ...

(1978). It is located in the Brownsville Commercial Historic District and supports Market Street, the local main thoroughfare. Due to the steep sides of the

Monongahela River The Monongahela River ( , ), sometimes referred to locally as the Mon (), is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map accessed August 15, 2011 river on the Allegheny Plateau in nor ...

valley, there is only room for two short streets parallel to the river's shore and graded mild enough to be comfortable to walk before the terrain rises too steeply for business traffic.

History

There have been four structures on this site. The first two collapsed in 1808 and 1820. The third, a wood-framed structure, needed replacement by 1832. This bridge is constructed using five parallel tubular ribs, each made of 9 elliptical segments to form the arch.

Notes

References

External links

Dunlap’s Creek Bridge: Historical Marker Database
* National Register nomination formbr>Dunlap's Creek Bridge: History and Heritage of Civil Engineering
* Bridges in Fayette County, Pennsylvania Road bridges on the National Register of Historic Places in Pennsylvania Historic American Engineering Record in Pennsylvania Historic Civil Engineering Landmarks National Register of Historic Places in Fayette County, Pennsylvania History of Fayette County, Pennsylvania Iron bridges in the United States Arch bridges in the United States National Road {{Pennsylvania-bridge-struct-stub

History

See also

Notes

References

External links