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HistoricBridges
This bridge is the oldest engineered structure in Washington County. The exact date is not known, but the National Road was through Washington County by 1818 and it is assumed that this bridge dates to that general time. |
When you are travelling at stagecoach speeds, it is not a big deal to put curves in the road so that the bridge is perpendicular to the flow of the water.
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| 2009 photo by Brian McKee via BridgeHunter |
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| 2009 photo by Brian McKee via BridgeHunter |
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| 2016 photo by Steve Conro via BridgeHunter |
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| 2018 photo by John Christeson via BridgeHunter |
Bridges & Tunnels by Sherman Cahal
posted four photos with the comment:
This S bridge was constructed in 1818 along the National Road in Washington County, Pennsylvania. Built with twin stone arch spans, it was bypassed in 1929 when U.S. Route 40 was realigned, a project that required the removal of its western approach. The bridge was otherwise preserved, though the loss remains visible today in the abrupt, truncated end of the crossing.
Aaron Carson: Why an "S" shape and not simply straight?
Dennis DeBruler: Aaron Carson Look at Sherman's third photo, so that they could cross the river at a 90-degree angle. That gives them the minimum span length needed to cross the river. I've noticed that was rather common for really old bridges. Remember, we are talking horse-&-buggy speeds, so a curve is not as significant.
https://maps.app.goo.gl/HuhqSwCxZwdr7QWC8 Bridges & Tunnels by Sherman Cahal
shared with the same comment.
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