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Trinity Hall

Washington, Washington County, Pennsylvania Listed Ref. 76001681 Building
Trinity Hall, Washington, Pennsylvania
Photo: Wjmoore17 (talk), CC BY 3.0, via Wikimedia Commons
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Why it's listed

Built in 1857 as a private residence in Washington, Pennsylvania, this large red brick house is a Tuscan Villa in the Italianate style. Its wings are low-pitched and decorated with dentils and coupled brackets, and the tall segmental arch windows have matching hood molds. A loggia of Tuscan columns with stilted arches runs along three sides of one wing, and a square wood cupola rises above the center gable, echoing an Italian Renaissance campanile. Joseph McKnight occupied the house until 1879, when William W. Smith, a Washington merchant and banker, bought it and funded its conversion into the Trinity Military Academy under Trinity Episcopal Church. A two-story addition by McKim, Mead and White was built at the rear in the late 1870s. The property was bought in 1925 by four surrounding townships and reopened as a public high school. A marble fireplace in one office records three visits by General Grant. The building is valued because the Italianate villa form is rare in Washington County.

Significance in brief: The nomination argues the building is an excellent example of the Tuscan Villa Italianate form, which it describes as rare in Washington County. It is also associated with the Trinity Military Academy and with a visit by General Grant, whose visits are recorded in a marble fireplace inscription.

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 76001681, listed September 27, 1976. Summary generated October 2026 (model claude-haiku-5-5, prompt v1.1-2026-10-29, confidence medium).

Key facts

Address1 mi. S of Washington on PA 18, Washington
CountyWashington County
ListedSeptember 27, 1976
Reference number76001681
Resource typeBuilding
Period of significance1857
Architect / builderMcKim, Mead and White (architects of the rear addition); T.V. Copeland (grounds)
Architectural styleItalianate; Tuscan Villa
Areas of significanceLandscape Architecture, Architecture
Level of significanceState
Status (as stated in the nomination)In continual use since construction; used primarily as the administration building for the Trinity School District.
Acreage1
Within districtWashington Commercial Historic District
Coordinates40.16479, -80.24868 (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

Last updated October 2026. Found an error? See the editorial policy for how to report it.