{"nrhp_refnum":"06001256","name":"Calver Island","other_names":["36da89"],"category":"site","location":{"address":null,"address_restricted":true,"city":"Swatara Township","county":"Dauphin County","state":"PA","lat":40.2056,"lon":-76.8067,"geom_source":"wikidata"},"listed_date":"2007-01-17","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Prehistoric"],"significance_levels":["state"],"summary":null,"photo":{"url_800":"https://nationalhistoricalregister.com/media/06001256/b689fed3a0-800.webp","url_1600":"https://nationalhistoricalregister.com/media/06001256/b689fed3a0-1600.webp","licence":"CC BY-SA 4.0","author":"Mapdudepa","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Calvers_Island.jpg\" rel=\"noopener\">Mapdudepa</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:Calvers_Island.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/71998329","wikipedia":"https://en.wikipedia.org/wiki/Calver_Island","wikidata":"https://www.wikidata.org/wiki/Q5024231"},"indexable":true,"url":"https://nationalhistoricalregister.com/pennsylvania/dauphin-county/calver-island-06001256/"}