{"nrhp_refnum":"87001502","name":"Three Sisters of Nauset (Twin Lights)","other_names":[],"category":"structure","location":{"address":"Off Cable Rd.","address_restricted":false,"city":"Eastham","county":"Barnstable County","state":"MA","lat":41.845115650000025,"lon":-69.95946075999996,"geom_source":"nps_gis"},"listed_date":"1987-06-15","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Engineering","Transportation","Architecture","Maritime History"],"significance_levels":["state"],"summary":{"what_it_is":"Two surviving 1892 wooden lighthouse towers, known as the Twin Lights or Three Sisters of Nauset, in Eastham, Barnstable County, Massachusetts, on a wooded lot off Cable Road near Coast Guard Beach.","why_significant":"The towers are significant for their association with the development of aids to navigation in Massachusetts. Built in 1892 as part of a trio of portable wooden towers replacing 1838 brick towers, they are described as the only example of a triple light, along with the Beacon. They illustrate an early, simple way of distinguishing nearby lights before one tower could hold three signals.","narrative":"Two small wooden lighthouse towers on a wooded lot off Cable Road in Eastham, near Coast Guard Beach, are what remain of the Three Sisters of Nauset, later called the Twin Lights. Built in 1892, they are two-story cylindrical, shingled wood-frame towers with lapstrake construction. They were made portable because the Nauset bluffs kept shifting, and they replaced three brick towers from 1838 that eventually washed onto the beach. In 1911 two of the three towers were sold, moved, and used as cottages. In 1920 the Cummings family relocated them and joined them with a cottage, which the National Park Service later demolished after buying the property in 1965. The lens rooms are gone, and the platforms now serve as roofs. The towers are valued for their setting, materials, and workmanship, and as the only example of a triple light, together with the Beacon. That arrangement was an early way to tell nearby lights apart, later made obsolete by revolving mechanisms.","period_of_significance":null,"architect_builder":null,"architectural_style":null,"criteria":["A","C"],"status_note":"Described as unmanned/inactive and somewhat deteriorated, with the lens rooms missing. The National Park Service demolished the connecting cottage and plans to move and restore the towers near their original site.","vacant_flag":null,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:13:01.193482-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/opastorage/live/59/7891/63789159/content/electronic-records/rg-079/NPS_MA/87001502.pdf"},"photo":null,"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/63789159","wikipedia":null,"wikidata":null},"indexable":true,"url":"https://nationalhistoricalregister.com/massachusetts/barnstable-county/three-sisters-of-nauset-twin-lights-87001502/"}