{"nrhp_refnum":"70000515","name":"Adena (Thomas Worthington House)","other_names":["Mount Prospect Hall"],"category":"building","location":{"address":"Box 831 Adena Rd.","address_restricted":false,"city":"Chillicothe","county":"Ross County","state":"OH","lat":39.35521942950007,"lon":-83.01360361301822,"geom_source":"nps_gis"},"listed_date":"1970-11-10","is_nhl":true,"nhl_designated_date":"2003-02-27","areas_of_significance":["Landscape Architecture","Politics/Government","Architecture"],"significance_levels":["national","state"],"summary":{"what_it_is":"Adena is an early nineteenth century stone mansion and hilltop plantation complex on West Allen Avenue extended, near Chillicothe in Scioto Township, Ross County, Ohio. Construction began in 1806 for Thomas Worthington, and the house was completed the next year.","why_significant":"The nomination argues Adena is significant for its association with Thomas Worthington, one of Ohio's first U.S. Senators and its sixth Governor, and for its architectural merit. Benjamin Henry Latrobe assisted in the design of the Early Federal mansion. The view from the site is said to have inspired the design of the Ohio State Seal.","narrative":"Adena is a stone mansion and former plantation on a hilltop near Chillicothe, Ohio, built for Thomas Worthington, who became one of Ohio's first U.S. Senators and its sixth Governor. Construction began in 1806, under the name Mount Prospect Hall, and the house was completed the next year. Worthington discussed his plans at length with Benjamin Henry Latrobe and Thomas Jefferson, and Latrobe assisted in the design. The three-part house has a two-story center section flanked by single-story wings that project forward to form a U, with restrained detailing and carefully varied hipped roofs. Gardens, a wash house, smoke house, ice house, servants' cottages, barns and a springhouse once formed a self-sufficient estate surrounded by fields and orchards. The view across the valley is said to have inspired the State Seal of Ohio. The property was given to the State of Ohio in 1946 and is now a museum. It was listed for its political association and architectural merit.","period_of_significance":"19th Century; specific date 1807","architect_builder":"Benjamin Henry Latrobe (assisted in the design)","architectural_style":"Early Federal","criteria":[],"status_note":"Excellent and unaltered condition; preserved and restored by The Ohio Historical Society and open to the public as a museum. The large barn and other outbuildings were being restored.","vacant_flag":false,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:53:09.973646-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_OH/70000515.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/70000515/32826167a7-800.webp","url_1600":"https://nationalhistoricalregister.com/media/70000515/32826167a7-1600.webp","licence":"CC BY-SA 3.0","author":"Analogue Kid (talk)","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Adena_Mansion.JPG\" rel=\"noopener\">Analogue Kid (talk)</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:Adena_Mansion.JPG"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/71991205","wikipedia":"https://en.wikipedia.org/wiki/Adena_Mansion","wikidata":"https://www.wikidata.org/wiki/Q4682182"},"indexable":true,"url":"https://nationalhistoricalregister.com/ohio/ross-county/adena-thomas-worthington-house-70000515/"}