{"nrhp_refnum":"78000282","name":"Radar Station B-71","other_names":["Klamath Ranger Station","Trinidad Radar Station","Klamath River"],"category":"building","location":{"address":"W of Klamath","address_restricted":false,"city":"Klamath","county":"Del Norte County","state":"CA","lat":41.52192407950005,"lon":-124.08045110783365,"geom_source":"nps_gis"},"listed_date":"1978-04-19","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Military","Architecture"],"significance_levels":["state"],"summary":{"what_it_is":"A World War II Army early warning radar station on a coastal shelf about two miles south of the mouth of the Klamath River in Del Norte County, California, built in late 1942 and early 1943 by a private contractor. It now lies within Redwood National Park.","why_significant":"The station is described as having regional architectural and military historical significance as a rare survivor of a World War II early warning radar station. Its buildings were designed with built-in camouflage, a farmhouse and a barn, which the form calls unusual. It was part of the pioneering radar air defense network on the Pacific Coast, and most of its sister stations have disappeared.","narrative":"Radar Station B-71, also called the Klamath River or Trinidad station, was an Army aircraft early warning post on a coastal shelf about 250 feet above the Pacific, two miles south of the Klamath River mouth. Built in late 1942 and early 1943, it was the northernmost California station in a Pacific Coast network of 65 stations actually built. Two thick concrete block buildings were designed to look like farm structures: a power building made to resemble a farmhouse, with false dormers and windows, and an operations building disguised as a barn. The form notes that building camouflage into new construction was unusual. A crew of about 35 men worked in shifts, and three machine guns protected the site. Converted to air-sea rescue service in July 1944, it stayed operational until the war's end, then reverted to ranch use. Decay, salvage, vandalism and mud slides have damaged it, yet it survives as a rare example of early American radar defenses.","period_of_significance":"1942","architect_builder":"Built for the Army by a private construction firm under Army contract (firm not named)","architectural_style":null,"criteria":[],"status_note":"Marked unoccupied. The buildings have decayed through vandalism, salvage and mud slides, and the privy is a partially collapsed ruin, but enough significant elements survive.","vacant_flag":true,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:55:32.200634-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_CA/78000282.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/78000282/80f17ece14-800.webp","url_1600":"https://nationalhistoricalregister.com/media/78000282/80f17ece14-1600.webp","licence":"CC BY-SA 4.0","author":"Ian Poellet","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:WW2_radar_station_1_-_Redwood_NP_California.jpg\" rel=\"noopener\">Ian Poellet</a>, <a href=\"https://creativecommons.org/licenses/by-sa/4.0\" rel=\"license noopener\">CC BY-SA 4.0</a>, via Wikimedia Commons","source_page":"https://commons.wikimedia.org/wiki/File:WW2_radar_station_1_-_Redwood_NP_California.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/123858593","wikipedia":"https://en.wikipedia.org/wiki/Radar_Station_B-71","wikidata":"https://www.wikidata.org/wiki/Q7279981"},"indexable":true,"url":"https://nationalhistoricalregister.com/california/del-norte-county/radar-station-b-71-78000282/"}