{"nrhp_refnum":"72001115","name":"Walnut Street Bridge","other_names":["See Also:Harrisburg Historic District"],"category":"structure","location":{"address":"Walnut St. over Susquehanna River","address_restricted":false,"city":"Harrisburg","county":"Dauphin County","state":"PA","lat":40.255082472000026,"lon":-76.88831716099997,"geom_source":"nps_gis"},"listed_date":"1972-06-05","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Engineering","Transportation"],"significance_levels":["national"],"summary":{"what_it_is":"A multispan wrought iron truss bridge carrying Walnut Street across the Susquehanna River at Harrisburg, Dauphin County, Pennsylvania, with a central island (City Island) dividing its length. The superstructure was fabricated by the Phoenix Bridge Co. of Phoenixville, Pennsylvania, and assembled on site by Dean & Westbrook of New York.","why_significant":"The bridge is regarded as one of the last surviving, if not the last, multispan bridges built with Phoenix columns in the East. It uses the Phoenix Column, a rolled wrought iron construction patented by Samuel Reeves from a design associated with Wendel Bollman. The form was among the most popular bridge types in the U.S. from about 1867 to the late 19th century, and the nomination considers it one of the best extant examples given its size and construction.","narrative":"Spanning the Susquehanna River at Harrisburg, Pennsylvania, the Walnut Street Bridge is an almost mile-long wrought iron truss structure, divided by City Island into seven spans of 175 feet to the west and four spans of 175 feet and three of 240 feet to the east. Its superstructure was fabricated by the Phoenix Bridge Co. of Phoenixville and assembled on site by Dean & Westbrook of New York, and it opened to traffic late in 1890. The longer spans cross the main channel, allowing passage for logging operations and coal barges. Its main members are built from rolled semicircular wrought iron sections riveted together, a patented method known as the Phoenix Column. This construction allowed bridges of almost any size to be assembled from standardized, prefabricated parts. The bridge is considered one of the last large wrought iron bridges and one of the last surviving multispan Phoenix bridges in the East, and it is regarded as among the best remaining examples of the type.","period_of_significance":"1889-1890","architect_builder":"Phoenix Bridge Co. (fabricator); Dean & Westbrook (erector)","architectural_style":null,"criteria":["A","C"],"status_note":"The present steel lattice flooring replaces the original wooden planks and steel guard rails have been welded to the sides; otherwise the bridge is described as very close to its original condition, in need of paint and some pier repair, and deemed sound, carrying about 8000 cars daily.","vacant_flag":false,"machine_generated":true,"model":"claude-haiku-5-5","prompt_version":"v1.1-2026-10-29","generated_at":"2026-10-29 17:11:30.371605-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_PA/72001115.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/72001115/c4c94d986f-800.webp","url_1600":"https://nationalhistoricalregister.com/media/72001115/c4c94d986f-1600.webp","licence":"CC BY-SA 3.0","author":"Kirkpatrick (talk)","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Peoples_bridge_Susquehanna.JPG\" rel=\"noopener\">Kirkpatrick (talk)</a>, <a href=\"http://creativecommons.org/licenses/by-sa/3.0/\" rel=\"license noopener\">CC BY-SA 3.0</a>, via Wikimedia Commons","source_page":"https://commons.wikimedia.org/wiki/File:Peoples_bridge_Susquehanna.JPG"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/71995823","wikipedia":"https://en.wikipedia.org/wiki/Walnut_Street_Bridge_(Harrisburg,_Pennsylvania)","wikidata":"https://www.wikidata.org/wiki/Q7963667"},"indexable":true,"url":"https://nationalhistoricalregister.com/pennsylvania/dauphin-county/walnut-street-bridge-72001115/"}