{"nrhp_refnum":"71000712","name":"Mount Joy","other_names":["Peter Legaux Mansion"],"category":"building","location":{"address":"North Lane and Hector St.","address_restricted":false,"city":"Conshohocken","county":"Montgomery County","state":"PA","lat":40.076905777000036,"lon":-75.28625753499995,"geom_source":"nps_gis"},"listed_date":"1971-03-11","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Industry","Science","Architecture","Philosophy","Agriculture"],"significance_levels":["national"],"summary":{"what_it_is":"Mount Joy, also known as the Legaux (Peter) Mansion, is a three-story house on the Schuylkill River near Spring Mill in Conshohocken, Montgomery County, Pennsylvania. The house was built about 1740, and the document attributes its original construction to Anthony Morris.","why_significant":"The nomination argues that the house is significant for its association with Peter Legaux, a French-born figure who lived there from 1786 and used it as a base for scientific, agricultural, and commercial work. It cites his membership in the American Philosophical Society, his vineyard and wine experiments, and visits by Washington and Jefferson. The surviving 18th-century interior woodwork and fireplaces are also noted as features of the house.","narrative":"Mount Joy is a three-story stone mansion above the Schuylkill River at Spring Mill in Conshohocken, Pennsylvania, built around 1740. Early records describe it as a marble house with ten large fire rooms and five cellars, and it passed through several owners, including Colonel Miles and George Mifflin, before Peter Legaux acquired it in 1786. Legaux laid out terraced gardens, kept beehives, operated a lime furnace and a public ferry, and planted experimental vineyards on the terraces. He was a member of the American Philosophical Society, and George Washington visited the property in 1787. The house retains ten fireplaces, some original iron firebacks, and much second-floor woodwork, and the terraces that remain are the main surviving trace of Legaux's vineyards.","period_of_significance":"c. 1740-1827","architect_builder":null,"architectural_style":null,"criteria":[],"status_note":null,"vacant_flag":null,"machine_generated":true,"model":"claude-haiku-5-5","prompt_version":"v1.1-2026-10-29","generated_at":"2026-10-29 17:11:31.020163-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_PA/71000712.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/71000712/64be11c3ff-800.webp","url_1600":"https://nationalhistoricalregister.com/media/71000712/64be11c3ff-1600.webp","licence":"CC0","author":"Smallbones","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Mount_Joy_Conshohocken_PA.jpg\" rel=\"noopener\">Smallbones</a>, <a href=\"http://creativecommons.org/publicdomain/zero/1.0/deed.en\" rel=\"license noopener\">CC0</a>, via Wikimedia Commons","source_page":"https://commons.wikimedia.org/wiki/File:Mount_Joy_Conshohocken_PA.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/71995138","wikipedia":"https://en.wikipedia.org/wiki/Mount_Joy_(Whitemarsh,_Pennsylvania)","wikidata":"https://www.wikidata.org/wiki/Q6921530"},"indexable":true,"url":"https://nationalhistoricalregister.com/pennsylvania/montgomery-county/mount-joy-71000712/"}