{"nrhp_refnum":"71000639","name":"Williamson Mound State Memorial","other_names":[],"category":"site","location":{"address":"Off OH 42","address_restricted":false,"city":"Cedarville","county":"Greene County","state":"OH","lat":39.74498821000003,"lon":-83.82678910699997,"geom_source":"nps_gis"},"listed_date":"1971-12-13","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Prehistoric"],"significance_levels":["state"],"summary":{"what_it_is":"An Adena burial mound in a small grassy park overlooking Massie Creek near Cedarville, Greene County, Ohio. It is now 27.5 feet high and 150 feet in diameter and was probably built between 500 B.C. and 400 A.D.","why_significant":"The nomination describes it as a large Adena mound that is likely to prove important archaeologically once fully excavated. Earlier digging was probably slight relative to the whole mound. If it was built over a long time, excavation could reveal changes in both burial practices and the daily life of the Adena people.","narrative":"Williamson Mound is a large Adena burial mound on a grassy rise above Massie Creek, near Cedarville in Greene County, Ohio. It now stands 27.5 feet high and about 150 feet across. The mound was probably built toward the end of the period between 500 B.C. and 400 A.D. It was given to the Ohio Historical Society in 1929 in three tracts, after which it was restored to its original shape, covering scars left by earlier explorations, including those of Squier and Davis in the 1840s. The nomination considers that digging to date was slight compared with the size of the mound. If the mound was raised over a long span of time, a full excavation might show changes in burial customs and in the everyday lives of the Adena people. The mound is regarded as likely to prove important archaeologically. The owner authorized transferring the site to the Greene County Park District as part of a new county park.","period_of_significance":"500 B.C.-400 A.D. (Pre-Columbian)","architect_builder":null,"architectural_style":null,"criteria":[],"status_note":"Condition listed as excellent; restored after earlier excavation scars were covered. Owned by the Ohio Historical Society, with a proposed transfer to the Greene County Park District. Form marks the site as unoccupied and as a park.","vacant_flag":null,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:53:09.85098-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_OH/71000639.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/71000639/3015f179e5-800.webp","url_1600":"https://nationalhistoricalregister.com/media/71000639/3015f179e5-1600.webp","licence":"Public domain","author":"Nyttend","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Williamson_Mound,_southern_side_comprehensive.jpg\" rel=\"noopener\">Nyttend</a>, Public domain, via Wikimedia Commons","source_page":"https://commons.wikimedia.org/wiki/File:Williamson_Mound,_southern_side_comprehensive.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/71988694","wikipedia":null,"wikidata":"https://www.wikidata.org/wiki/Q115110581"},"indexable":true,"url":"https://nationalhistoricalregister.com/ohio/greene-county/williamson-mound-state-memorial-71000639/"}