Spring Grove Forge Mansion
Why it's listed
Built of local stone on a rise above the Conestoga River in East Earl Township, Lancaster County, Spring Grove Forge Mansion took shape in three stages between 1789 and 1830 for the ironmaster Cyrus Jacobs. The L-shaped two-story house has a six bay south facade with a gouge carved piazza, believed to date from about 1805 to 1815, that carries carved mouldings and fretwork friezes. Its interior holds plasterwork ceiling medallions, several marble mantels from about 1820 to 1830, and a Federal mantel of about 1810 with bamboo turned engaged columns. The northeast second-floor chamber keeps its original Georgian woodwork from about 1790, including built-in drawers beneath the cupboards. The west kitchen wing is believed to predate 1764, when Thomas Edwards died. The house is regarded as the most intact of Jacobs' houses and a record of the county's wealthy iron manufacturing.
Significance in brief: The nomination argues the house is significant for its architecture and as a monument to Lancaster County's iron industry. It is described as the most intact of at least six houses built for Cyrus Jacobs, and as the only ironmaster's mansion in the county showing three architectural styles in one building. Its gouge carved piazza is presented as a unique survival with no larger or finer example known in the county.
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 84003447, listed July 11, 1984. Summary generated October 2026 (model claude-haiku-5-5, prompt v1.1-2026-10-29, confidence medium).
Key facts
| Address | Spring Grove Rd., East Earl |
|---|---|
| County | Lancaster County |
| Listed | July 11, 1984 |
| Reference number | 84003447 |
| Resource type | Building |
| Period of significance | Pre 1789 - c. 1830 |
| Architectural style | Georgian, Federal and Classical Revival |
| Areas of significance | Industry, Architecture |
| Level of significance | Local |
| Status (as stated in the nomination) | Remarkably intact to its state at the time of Cyrus Jacobs' death in 1830; the sun porch is a c. 1930 addition. |
| Acreage | 1.9 |
| Coordinates | 40.14491, -76.02101 (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 84003447.
- Nomination form (PDF, National Archives) — catalog entry
- Wikipedia article (used for cross-checking only; text not reproduced here)
- Wikidata Q7580539
- This listing as JSON
Last updated October 2026. Found an error? See the editorial policy for how to report it.