{"nrhp_refnum":"86000017","name":"Sixth Street Bridge","other_names":[],"category":"structure","location":{"address":"Allegheny River at Sixth St.","address_restricted":false,"city":"Pittsburgh","county":"Allegheny County","state":"PA","lat":40.44528746200007,"lon":-80.00314416599997,"geom_source":"nps_gis"},"listed_date":"1986-01-07","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Engineering","Transportation","Politics/Government"],"significance_levels":["national"],"summary":{"what_it_is":"The Sixth Street Bridge is a steel self-anchored suspension bridge crossing the Allegheny River between downtown Pittsburgh and the North Side, in Allegheny County, Pennsylvania. It was erected in 1927-28 by Allegheny County.","why_significant":"The nomination argues the bridge is significant as one of the first self-anchored suspension bridges in the United States, and as one of the only important surviving examples of the eyebar suspension bridge in the country. It is one of three nearly identical bridges, along with the Seventh and Ninth Street Bridges, which the document describes as the nation's only trio of virtually identical spans. It was also built as part of a large county public works program of the 1920s and 1930s.","narrative":"Spanning the Allegheny River between downtown Pittsburgh and the North Side, the Sixth Street Bridge is a steel self-anchored suspension bridge completed in 1927-28 by Allegheny County. Its two towers have rounded arched openings and carry eyebar catenaries pinned at the towers and anchored at stone shoreline piers. The deck is stiffened by triple web plate girders, and the original roadway carried trolleys alongside motor vehicles. The bridge is one of three nearly identical spans built together with the Seventh and Ninth Street Bridges, which were erected to meet War Department navigation requirements. Its design is attributed to County Engineer Vernon R. Covell, while Stanley Roush is credited with the architectural work. The bridge occupies the site of an earlier crossing and incorporates masonry from it. It is regarded as one of the most significant river crossings in the city and among the few surviving examples of its type.","period_of_significance":"1921-1940","architect_builder":"Vernon R. Covell et al. (engineer); Stanley Roush (architect); The Foundation Co. and American Bridge Co. (contractors)","architectural_style":"Suspension Bridge (Self-anchored)","criteria":[],"status_note":"Condition recorded as good and integrity as excellent on the survey form.","vacant_flag":null,"machine_generated":true,"model":"claude-haiku-5-5","prompt_version":"v1.1-2026-10-29","generated_at":"2026-10-29 17:11:33.438386-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_PA/86000017.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/86000017/1b3bfd99d1-800.webp","url_1600":"https://nationalhistoricalregister.com/media/86000017/1b3bfd99d1-1600.webp","licence":"CC BY-SA 2.0","author":"David Trainer from Mosteiros, Cape Verde","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Roberto_Clemente_bridge.jpg\" rel=\"noopener\">David Trainer from Mosteiros, Cape Verde</a>, <a href=\"https://creativecommons.org/licenses/by-sa/2.0\" rel=\"license noopener\">CC BY-SA 2.0</a>, via Wikimedia Commons","source_page":"https://commons.wikimedia.org/wiki/File:Roberto_Clemente_bridge.jpg"},"district":{"nrhp_refnum":"13000250","name":"Penn-Liberty Historic District (Boundary Increase)","url":"https://nationalhistoricalregister.com/districts/pennsylvania/penn-liberty-historic-district-boundary-increase-13000250/"},"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/71992234","wikipedia":"https://en.wikipedia.org/wiki/Roberto_Clemente_Bridge","wikidata":"https://www.wikidata.org/wiki/Q7351643"},"indexable":true,"url":"https://nationalhistoricalregister.com/pennsylvania/allegheny-county/sixth-street-bridge-86000017/"}