{"nrhp_refnum":"90001621","name":"Knabb-Bieber Mill","other_names":["John Knabb Mill","See Also:Oley Township Historic District"],"category":"building","location":{"address":"Bieber Mill Rd. at Monocacy Cr., Oley Township","address_restricted":false,"city":"Stony Creek Mills","county":"Berks County","state":"PA","lat":40.358879764500045,"lon":-75.81018776566953,"geom_source":"nps_gis"},"listed_date":"1990-11-08","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Industry","Engineering","Architecture"],"significance_levels":["local"],"summary":{"what_it_is":"A stone gristmill on Monocacy Creek in Stony Creek Mills, Oley Township, Berks County, Pennsylvania, with an attached wagon scale, a weigh house and a stone-and-frame icehouse. The mill is dated by a painted inscription and the document gives 1809 as its construction year.","why_significant":"The nomination argues the mill is significant for its direct association with grain milling in Berks County and as an early 19th-century merchant mill with Georgian architectural detail. It also stresses the building's structural integrity, its surviving evidence of changing milling technology, and its last traditional one-man operator.","narrative":"Built in 1809 on Monocacy Creek in Stony Creek Mills, the Knabb-Bieber Mill is a two and one-half story stone gristmill with a basement, measuring 40 feet 4 inches by 54 feet 6 inches. Its Georgian features include pedimented doorways, pent roofs at the gable ends and panelled Dutch doors. Its windows sit at different heights to light the wheel pit, stone floor and office, which reflects the several levels the machinery required. Inside, massive summer beams, beaded joists and a German-style trussed roof show heavy construction built to carry stored grain. The mill retains two pairs of French-style millstones driven by a turbine, and it was never converted to roller milling. A surviving wagon scale and weigh house from the 1930s remain in use. The building is regarded as a well-preserved example of an early merchant mill and its working equipment, and it is valued for its integrity and engineering.","period_of_significance":"1809-1939","architect_builder":null,"architectural_style":"Georgian","criteria":["A","C","D"],"status_note":"Operating gristmill; the document states the mill is still actively used and its water courses were recently restored.","vacant_flag":false,"machine_generated":true,"model":"claude-haiku-5-5","prompt_version":"v1.1-2026-10-29","generated_at":"2026-10-29 17:11:37.784601-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_PA/90001621.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/90001621/2e3e82ec11-800.webp","url_1600":"https://nationalhistoricalregister.com/media/90001621/2e3e82ec11-1600.webp","licence":"Public domain","author":"Cervin Robinson","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Knabb-Bieber_Mill.jpg\" rel=\"noopener\">Cervin Robinson</a>, Public domain, via Wikimedia Commons","source_page":"https://commons.wikimedia.org/wiki/File:Knabb-Bieber_Mill.jpg"},"district":{"nrhp_refnum":"83002218","name":"Oley Township Historic District","url":"https://nationalhistoricalregister.com/districts/pennsylvania/oley-township-historic-district-83002218/"},"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/71992328","wikipedia":"https://en.wikipedia.org/wiki/Knabb-Bieber_Mill","wikidata":"https://www.wikidata.org/wiki/Q6421707"},"indexable":true,"url":"https://nationalhistoricalregister.com/pennsylvania/berks-county/knabb-bieber-mill-90001621/"}