{"nrhp_refnum":"84000767","name":"Clayton Vineyards-DeMartini Winery","other_names":["Forni Ranch,Clayton Ranch"],"category":"building","location":{"address":"5919 Clayton Rd.","address_restricted":false,"city":"Clayton","county":"Contra Costa County","state":"CA","lat":37.94293591600007,"lon":-121.93755129099998,"geom_source":"nps_gis"},"listed_date":"1984-08-30","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Industry","Historic - Aboriginal","Exploration/Settlement","Architecture","Agriculture"],"significance_levels":["local"],"summary":{"what_it_is":"An 8.328-acre parcel at 5919 Clayton Road in Clayton, Contra Costa County, California, holding the 1885 DeMartini Winery, a three-storey sandstone and wood building, on the remaining part of a 1860s vineyard.","why_significant":"The nomination ties the property to Joel Clayton, who founded the town and planted Clayton Vineyards around 1863, and to Paul DeMartini, who built the winery in 1885. It became the second largest winery in the county and won first prizes for port and sherry at the 1903 St. Louis fair. The building is also one of the few surviving examples of the county's pre-Prohibition wine industry.","narrative":"Set on an 8.328-acre parcel along Clayton Road, this 1885 winery is a 50-by-66-foot, three-storey building cut into a hillside. Its lower two floors are two-foot-thick sandstone, and the upper floor and roof are wood frame with shiplap siding and shingles. Stonemasons Dragovitch and Cavagnaro built it for Paul DeMartini, who had taken over the vineyard planted around 1863 by Joel Clayton, the founder of the town. By 1897 the winery ranked second in Contra Costa County for output, and its port and sherry won first prizes at the 1903 St. Louis fair. Prohibition ended winemaking in 1920, and the land was turned to almonds. The building later served as storage and a residence, then was abandoned in 1979 and suffered vandalism. The Sherry House and other early structures are gone. It survives as one of the few winery buildings left from the county's early wine industry.","period_of_significance":"1800-1899","architect_builder":"Dragovitch and Cavagnaro","architectural_style":null,"criteria":[],"status_note":"Abandoned in 1979 and vandalized afterward; some sandstone deterioration noted. The owner at the time planned restoration.","vacant_flag":true,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:54:27.421826-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_CA/84000767.pdf"},"photo":null,"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/123858512","wikipedia":null,"wikidata":null},"indexable":true,"url":"https://nationalhistoricalregister.com/california/contra-costa-county/clayton-vineyards-demartini-winery-84000767/"}