{"nrhp_refnum":"76000247","name":"Thoreau-Alcott House","other_names":[],"category":"building","location":{"address":"255 Main St.","address_restricted":false,"city":"Concord","county":"Middlesex County","state":"MA","lat":42.45845219000006,"lon":-71.35791051699994,"geom_source":"nps_gis"},"listed_date":"1976-07-12","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Literature","Philosophy","Social History"],"significance_levels":["national"],"summary":{"what_it_is":"A two-story clapboard house at 255 Main Street in Concord, Massachusetts, built around 1820 by builder Josiah Davis and later enlarged with a south wing in 1849 and a west wing in 1877.","why_significant":"It was the home of Henry David Thoreau from 1849 until his death in 1862, the period in which he wrote Walden and Cape Cod, and it housed the family pencil business. In 1877 Louisa May Alcott helped buy it for her parents and her sister's family, linking it to the Alcott family and the School of Philosophy. It has changed very little since the 1880s.","narrative":"Set back from Main Street in Concord behind a tall hemlock hedge, this clapboard house was built around 1820 by the local builder Josiah Davis. In 1849 John Thoreau and his son Henry David renovated it, adding a pedimented portico with Doric columns, a mahogany stair railing and a south wing for the family pencil factory. Henry David Thoreau lived here during his most productive years, writing Walden and Cape Cod, and died in the front parlor in 1862. In 1877 the house was sold to Anna Alcott Pratt. Louisa May Alcott, by then financially successful, paid most of the cost and funded a west wing with a library and a porch. Her parents Bronson and Abigail Alcott moved in, and the library hosted meetings of the School of Philosophy. The house has changed little since the 1880s, apart from its paint color and the removal of an outside staircase.","period_of_significance":"1800-1899","architect_builder":"Josiah Davis","architectural_style":"Greek Revival","criteria":[],"status_note":"Occupied as a private residence, in good condition, and described as virtually unaltered since the 1880s.","vacant_flag":false,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:11:54.644868-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/opastorage/live/58/7961/63796158/content/electronic-records/rg-079/NPS_MA/76000247.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/76000247/dce57e8b35-800.webp","url_1600":"https://nationalhistoricalregister.com/media/76000247/dce57e8b35-1600.webp","licence":"CC BY-SA 3.0","author":"John Phelan","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Thoreau_Alcott_House,_Concord_MA.jpg\" rel=\"noopener\">John Phelan</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:Thoreau_Alcott_House,_Concord_MA.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/63796158","wikipedia":"https://en.wikipedia.org/wiki/Thoreau%E2%80%93Alcott_House","wikidata":"https://www.wikidata.org/wiki/Q7796188"},"indexable":true,"url":"https://nationalhistoricalregister.com/massachusetts/middlesex-county/thoreau-alcott-house-76000247/"}