One of the few bridges in Historic Bridges that have the rating of two 10/10. The oldest bridge in the USA is the 1839 Market Street Bridge. It is an arch bridge so all of its structural members can be made with cast iron. This bridge needs wrought iron for its tension members.
Significance: The Reading-Halls Bridge is almost certainly the oldest all-metal truss bridge in active service in the United States, a lone survivor from the first series of all-metal trusses of any kind designed and constructed in the United States. This Howe pony through-truss bridge followed shortly after the construction in 1845 of the very first all-metal truss bridge, the West Manayunk Bridge, also designed by Osborne and built by the Reading Railroad. [HAER_data]
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| HAER PA,41-MUNC.V,1--1 1. Credit JTL: West elevation of bridge - Reading-Halls Station Bridge, U.S. Route 220, spanning railroad near Halls Station, Muncy, Lycoming County, PA |
I was going to label this a bridgeTrussPin since it is an old bridge. But then I noticed that this bridge uses cast-iron compression members so it uses is an even older connection technology. It essentially uses friction for the joints under compression and nuts-and-bolts for the tension members. I presume the tension members are made from wrought iron.
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| HAER PA,41-MUNC.V,1--8 8. Credit JTL: Detail view, six panels at south end of eastern truss, from beside bridge |
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| 14:42 video @ 1:23 (source) The history starts here. The bridge is owned by the farmer that owns the land, not the railroad. But the railroad has done most of the maintenance. |
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