{"nrhp_refnum":"73001187","name":"Prudential Building","other_names":["Guaranty Building"],"category":"building","location":{"address":"Church and Pearl Sts.","address_restricted":false,"city":"Buffalo","county":"Erie County","state":"NY","lat":42.88308799650005,"lon":-78.87678524867592,"geom_source":"nps_gis"},"listed_date":"1973-03-20","is_nhl":true,"nhl_designated_date":"1975-05-15","areas_of_significance":["Commerce","Architecture"],"significance_levels":["national"],"summary":{"what_it_is":"A thirteen-story steel-frame commercial office building at the southwest corner of Church and Pearl Streets in Buffalo's central business district, built in 1894-1895 and designed by Louis Sullivan.","why_significant":"The nomination cites architectural historians who rank it among Louis Sullivan's most significant works and a milestone in modern architecture. It joins a steel skeleton with a skin of lace-like terra cotta ornament and serves as a bridge between nineteenth- and twentieth-century skyscraper design. Its surroundings have not been crowded by taller buildings, and its terra cotta is well preserved thanks to Buffalo's cleaner air.","narrative":"Rising thirteen stories at Church and Pearl Streets in downtown Buffalo, this office block was designed by Louis Sullivan and built in 1894-1895. Commissioned by the Chicago Guaranty Trust Company, it was originally called the Guaranty Building. A steel frame is sheathed in decorative terra cotta, with vertical bands of windows, arches at the twelfth floor, circular windows on the thirteenth, and an overhanging cornice. Inside, the rear lobby keeps its cast iron and leaded glass skylight, a mosaic frieze and a cast iron stairway. Architectural historians, including Henry-Russell Hitchcock, regard it as Sullivan's masterpiece and a link between two eras of skyscraper design. Its unity of design remains clear because taller neighbors have not crowded it, and its terra cotta has weathered better than comparable work in Chicago. Ground-floor shop windows were altered around 1970, but the upper facades remain largely as built.","period_of_significance":"1894-1895","architect_builder":"Louis Sullivan (commissioned by the Chicago Guaranty Trust Company)","architectural_style":null,"criteria":[],"status_note":"Condition listed as excellent and altered; ground-floor store windows were changed around 1970. The form also lists the building as occupied.","vacant_flag":false,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:50:39.402095-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_NY/73001187.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/73001187/4d3bf64b87-800.webp","url_1600":"https://nationalhistoricalregister.com/media/73001187/4d3bf64b87-1600.webp","licence":"CC BY-SA 3.0","author":"geoffmcc","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Prudential_Building_2013-09-08_12-21-41.jpg\" rel=\"noopener\">geoffmcc</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:Prudential_Building_2013-09-08_12-21-41.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/75317677","wikipedia":"https://en.wikipedia.org/wiki/Prudential_Building_(Buffalo,_New_York)","wikidata":"https://www.wikidata.org/wiki/Q3778256"},"indexable":true,"url":"https://nationalhistoricalregister.com/new-york/erie-county/prudential-building-73001187/"}