{"nrhp_refnum":"75001640","name":"Rockville Bridge","other_names":[],"category":"structure","location":{"address":"0.5 mi. S of Marysville over Susquehanna River","address_restricted":false,"city":"Marysville","county":"Dauphin County","state":"PA","lat":40.33307842700003,"lon":-76.91132611899997,"geom_source":"nps_gis"},"listed_date":"1975-08-15","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Engineering","Transportation"],"significance_levels":["national"],"summary":{"what_it_is":"A four-track stone masonry arch railroad bridge carrying the Pennsylvania Railroad across the Susquehanna River just north of Harrisburg, Pennsylvania, roughly 3280 feet long. It was built during 1900-1902.","why_significant":"At the time of construction it was the longest stone masonry arch railroad bridge in the world. It replaced an inadequate double-track iron bridge on the Main Line of the Pennsylvania Railroad and remains in use by the Penn Central Railroad.","narrative":"Across the Susquehanna River just north of Harrisburg, Pennsylvania, a four-track railroad bridge runs about 3280 feet on forty-eight stone arch spans of seventy feet each. Built between 1900 and 1902 for the Pennsylvania Railroad, it uses cut-stone voussoirs, ashlar pier faces, and about 100,000 cubic yards of masonry. The bridge replaced an earlier double-track iron structure built in 1877 that was judged inadequate for the traffic on the Main Line. The eastern half was built by Drake and Stratton of Philadelphia and the western half by H.S. Kerbaugh, Inc., also of Philadelphia, at a total cost of about $1,096,000. Completed by March 30, 1902, it was at that time the longest stone masonry arch railroad bridge in the world. Its springing line sits near the level of the great flood of 1889. It remains in service with the Penn Central Railroad.","period_of_significance":null,"architect_builder":"Drake and Stratton (Philadelphia), eastern half; H.S. Kerbaugh, Inc. (Philadelphia), western half","architectural_style":null,"criteria":[],"status_note":"Still in use by the Penn Central Railroad; condition marked good.","vacant_flag":false,"machine_generated":true,"model":"claude-haiku-5-5","prompt_version":"v1.1-2026-10-29","generated_at":"2026-10-29 17:11:29.276551-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_PA/75001640.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/75001640/02aa950c0c-800.webp","url_1600":"https://nationalhistoricalregister.com/media/75001640/02aa950c0c-1600.webp","licence":"CC BY-SA 2.0","author":"Don Kasak from St. Louis, MO, US","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Rockville_Bridge_03.jpg\" rel=\"noopener\">Don Kasak from St. Louis, MO, US</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:Rockville_Bridge_03.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/71996414","wikipedia":"https://en.wikipedia.org/wiki/Rockville_Bridge","wikidata":"https://www.wikidata.org/wiki/Q2160784"},"indexable":true,"url":"https://nationalhistoricalregister.com/pennsylvania/dauphin-county/rockville-bridge-75001640/"}