{"nrhp_refnum":"87000666","name":"Ehrhart's Mill Historic District","other_names":[],"category":"district","location":{"address":"Old Mill Rd.","address_restricted":false,"city":"Hellertown","county":"Northampton County","state":"PA","lat":40.56197082700004,"lon":-75.34896924799995,"geom_source":"nps_gis"},"listed_date":"1987-04-30","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Commerce","Engineering","Architecture"],"significance_levels":["state"],"summary":{"what_it_is":"A historic district along Old Mill Road beside Saucon Creek in Lower Saucon Township, Northampton County, Pennsylvania, centered on a stone grist mill and including two houses, a farmhouse, outbuildings and County Bridge #16. Its buildings and structures date largely from the nineteenth century.","why_significant":"The grist mill is described as the largest late-nineteenth and early twentieth century grist mill on Saucon Creek and the only one in southern Northampton County that retains all its nineteenth century milling equipment. County Bridge #16, an iron Pratt truss bridge erected in 1867, is described as the earliest known iron Pratt truss bridge in Pennsylvania. The district also holds locally important rural architecture.","narrative":"Along Old Mill Road beside Saucon Creek in Lower Saucon Township stands a cluster of nineteenth-century buildings centred on a limestone grist mill. The mill, rebuilt after a fire in 1865 under a gambrel roof, still holds three runs of mill stones, a 42-inch turbine that replaced an earlier water wheel around 1900, and most of its nineteenth-century milling machinery, which is rare among surviving local mills. The district also includes a mill house, a brick retirement house, a limestone farmhouse of about 1850, outbuildings, and an iron Pratt truss bridge completed in 1867. Its significance rests on that bridge, regarded as the earliest known iron Pratt truss bridge in Pennsylvania and a forerunner of a design later used widely across the state, and on the mill's unusually complete equipment. The houses, built by members of one family, are a locally notable mix of stone and brick construction.","period_of_significance":"1800-1937","architect_builder":null,"architectural_style":null,"criteria":["A","C"],"status_note":"The bridge has been closed to vehicular traffic since 1983 after a beam cracked, and the district is described as endangered by a township plan to demolish the bridge.","vacant_flag":null,"machine_generated":true,"model":"claude-haiku-5-5","prompt_version":"v1.1-2026-10-29","generated_at":"2026-10-29 17:13:32.141483-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_PA/87000666.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/87000666/c6c86554a2-800.webp","url_1600":"https://nationalhistoricalregister.com/media/87000666/c6c86554a2-1600.webp","licence":"CC BY-SA 3.0","author":"JERRYE &amp; ROY KLOTZ MD","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:EHRHART%27S_MILL_HISTORIC_DISTRICT.jpg\" rel=\"noopener\">JERRYE &amp;amp; ROY KLOTZ MD</a>, <a href=\"https://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:EHRHART%27S_MILL_HISTORIC_DISTRICT.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/71996343","wikipedia":"https://en.wikipedia.org/wiki/Ehrhart%27s_Mill_Historic_District","wikidata":"https://www.wikidata.org/wiki/Q5348621"},"indexable":true,"url":"https://nationalhistoricalregister.com/pennsylvania/northampton-county/ehrharts-mill-historic-district-87000666/"}