Harden, Edward, Mansion
Also known as: Broad Oaks
Why it's listed
Broad Oaks, the Edward Harden Mansion, is a two-and-one-half story red brick Georgian Revival house on a hill above the Hudson River in Sleepy Hollow, New York. Built in 1909 and designed by Richard Howland Hunt and Joseph Howland Hunt of Hunt & Hunt, it has a symmetrical seven-bay façade, slate hip roof with dormers, marble trim, and two-story enclosed wood porches on its flanks. Inside, original black walnut woodwork, mantels and plaster detailing survive. A c. 1880 carriage house also remains on the site. Harden was a financier and former journalist known for sending news of Admiral Dewey's victory at Manila Bay. In 1911 part of the house hosted a Montessori kindergarten, described as the first in America. Later the building served as a home for retired seamstresses, then passed to the local board of education in 1955. It now houses the school district's offices. Its architecture and Montessori history underpin its listing.
Significance in brief: The nomination argues the house is an outstanding example of Georgian Revival residential architecture in Westchester County, designed by Hunt & Hunt. It also claims significance in education as the site of the first Montessori school in America, begun in 1911 with the Harden children among the first students.
Machine-generated summary. This summary was generated by a language model from the official nomination document and has not been reviewed line by line by an editor. It may contain errors. Check the source document before relying on any detail. Source: nomination document (PDF) · National Archives catalog entry. NRHP reference 03001401, listed January 16, 2004. Summary generated October 2026 (model claude-sonnet-5-5, prompt v1.0-2026-10-29, confidence high).
Key facts
| Address | 200 North Broadway, Sleepy Hollow |
|---|---|
| County | Westchester County |
| Listed | January 16, 2004 |
| Reference number | 03001401 |
| Resource type | Building |
| Period of significance | c. 1880 - 1912 |
| Architect / builder | Hunt & Hunt |
| Architectural style | Late 19th & 20th Century Revivals: Georgian Revival |
| Criteria |
|
| Areas of significance | Architecture, Education |
| Level of significance | Local |
| Status (as stated in the nomination) | Converted from a home into offices and now serves as the administration building for the Union Free School District of the Tarrytowns; most original exterior and interior features remain intact. |
| Acreage | 0.9 |
| Coordinates | 41.08285, -73.85731 (NPS GIS) |
What listing means for this property
National Register listing is honorary for a privately owned home: it does not by itself restrict what an owner may do with their own money, and it does not require public access. Restrictions come from local landmark or historic-district ordinances, which are separate (how they differ).
Owner-occupied houses are not eligible for the 20% federal rehabilitation tax credit, which applies to income-producing buildings, but many states offer credits for homeowners. Listing also opens the door to preservation easements and to buying a plaque. Start with what listing means for homeowners, renovating a listed house and selling one.
General information, not legal or tax advice. Rules change; confirm with your State Historic Preservation Office or a qualified adviser.
Sources and further reading
- National Park Service, National Register of Historic Places database (snapshot May 2026), reference 03001401.
- Nomination form (PDF, National Archives) — catalog entry
- Wikipedia article (used for cross-checking only; text not reproduced here)
- Wikidata Q5343306
- This listing as JSON
Last updated October 2026. Found an error? See the editorial policy for how to report it.