{"nrhp_refnum":"77000972","name":"Castle Rock","other_names":[],"category":"district","location":{"address":"NY 9D","address_restricted":false,"city":"Garrison","county":"Putnam County","state":"NY","lat":41.369701346000056,"lon":-73.93747606937995,"geom_source":"nps_gis"},"listed_date":"1977-12-12","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Architecture"],"significance_levels":["state"],"summary":{"what_it_is":"Castle Rock is an estate district of about 128 acres in Garrison, Putnam County, New York, centered on a stone mansion built in 1881 on a ridge above the Hudson River. It includes the mansion and numerous related houses, barns, and outbuildings.","why_significant":"The mansion was designed by New York architect J. Morgan Slade for William H. Osborn, president of the Illinois Central Railroad, and is described as one of the Hudson Highlands' most striking landmarks embodying the picturesque ideal. The estate was later home to Henry Fairfield Osborn, a prominent paleontologist, who enlarged the house in 1906 in a matching style. The estate has changed little since then.","narrative":"Castle Rock is a large estate on a high ridge on the east bank of the Hudson River in Garrison, across from West Point and Highland Falls. Its centerpiece is a thirty-four room, rough-cut stone mansion completed in 1881 and designed by New York architect J. Morgan Slade for William H. Osborn, president of the Illinois Central Railroad. A round tower with a conical roof, red slate roofing, dormers, porches and galleries give the house an irregular, eclectic profile. Osborn's son, the paleontologist Henry Fairfield Osborn, added a north wing and library in 1906, along with a stone arch bridge and caretaker's cottage, matching the original design. The nominated district of about 128 acres also holds Woodsome Lodge, Lilac Cottage, a gatehouse, barns, root cellars, the older Wing and Wing farmhouse, and winding driveways with dry masonry walls. It was listed because of its architecture, its landmark setting, and its association with the Osborn family.","period_of_significance":"1881","architect_builder":"J. Morgan Slade","architectural_style":"Historically eclectic, picturesque style","criteria":[],"status_note":"Condition listed as good, altered, original site; still owned by heirs of the original owner and used as private residences.","vacant_flag":false,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:50:40.123565-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_NY/77000972.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/77000972/d26aae9055-800.webp","url_1600":"https://nationalhistoricalregister.com/media/77000972/d26aae9055-1600.webp","licence":"CC BY-SA 3.0","author":"HarryShuldman","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:CastleRockGarrison.jpg\" rel=\"noopener\">HarryShuldman</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:CastleRockGarrison.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/75321024","wikipedia":"https://en.wikipedia.org/wiki/Castle_Rock_(Garrison,_New_York)","wikidata":"https://www.wikidata.org/wiki/Q5050262"},"indexable":true,"url":"https://nationalhistoricalregister.com/new-york/putnam-county/castle-rock-77000972/"}