{"nrhp_refnum":"08000086","name":"Torpedo Storehouse-Torpedo (Mine) Assembly Building & Long Range Accuracy Storage Building","other_names":["Building 262"],"category":"building","location":{"address":"N. of I80","address_restricted":false,"city":"Yerba Buena Island","county":"San Francisco","state":"CA","lat":37.81475762200006,"lon":-122.35939997799994,"geom_source":"nps_gis"},"listed_date":"2008-06-11","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Military","Architecture"],"significance_levels":["state"],"summary":{"what_it_is":"A one-story reinforced concrete torpedo (submarine mine) storehouse and assembly building, Building 262, at East Point on Yerba Buena Island in San Francisco Bay, completed in 1891 for the U.S. Army.","why_significant":"It is the only surviving building the Army constructed on Yerba Buena Island, and it records the growth of the military presence there (Criterion A). It is also a rare early reinforced concrete building and a representative work of Ernest Leslie Ransome, built with his patented stone-like wall finishing method (Criterion C).","narrative":"Building 262 is a one-story reinforced concrete structure at East Point on Yerba Buena Island, close to the San Francisco-Oakland Bay Bridge. Completed in 1891, it measures 158 by 72 feet, with 24-foot walls and a symmetrical Neo-Classical design featuring arched doorways and multi-light wood windows. It was built to store and assemble torpedoes, then the term for submarine mines, after earlier torpedoes rusted in storage on Alcatraz. Army engineer George Mendell first planned a brick shed, but rising brick prices led him to turn to reinforced concrete and to engineer Ernest Ransome. The walls were cast in patterned molds and tooled to resemble rusticated stone under Ransome's patented method. The San Francisco firm Percy and Hamilton may have collaborated on the design, though documentation is lacking. The building is the only surviving Army-built structure on the island, and it is a rare early example of reinforced concrete construction. It later served as a Long Range Accuracy storage facility from 1953 and is now vacant.","period_of_significance":"1891-1953","architect_builder":"Ransome, Ernest Leslie; Ransome and Cushing; Percy, George W.; Percy and Hamilton; Hamilton, F.F.","architectural_style":"Late 19th Century Revival: Classical Revival - Neo-Classical Revival","criteria":["A","C"],"status_note":"Listed current function is vacant/not in use; original window glazing is partly covered by protective wood shutters installed by the Navy during base layaway.","vacant_flag":true,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:54:29.717753-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_CA/08000086.pdf"},"photo":null,"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/123861333","wikipedia":null,"wikidata":null},"indexable":true,"url":"https://nationalhistoricalregister.com/california/san-francisco/torpedo-storehouse-torpedo-mine-assembly-building-and-long-range-accuracy-storag-08000086/"}