McClay's Twin Bridge (West)
Also known as: McClay's Bridge (East)
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Why it's listed
Built in 1827 by Silas Harry, a Pennsylvania master mason, this three-arch stone bridge crosses Conodoguinet Creek between Southampton and Lurgan Townships in Franklin County. It measures about 177 feet overall, with a central arch of 31 feet and two flanking arches of 29 feet each. Its wings curve outward and widen at the approaches, and its stone parapet has a concrete cap. A second bridge stands alongside it on the same road, and the two are commonly known as McClay's Twin Bridges. Harry also built stone bridges along the National Road in Pennsylvania and Maryland. The bridge is valued as a very fine example of a long, multiple-span turnpike bridge from the early nineteenth century. Its roughly coursed local limestone, semi-pyramidal piers and coping reflect construction methods typical of Franklin County bridges built before 1860. Few stone bridges from that county survive, which adds to its importance. The structure was altered in 1982 but retains its essential character.
Significance in brief: The nomination describes it as a very fine example of a long, multiple-span nineteenth-century turnpike bridge. Its roughly coursed local limestone, semi-pyramidal piers and coping are presented as typical of Franklin County bridges built before 1860. Silas Harry is described as one of Pennsylvania's master masons who built stone bridges along the National Road in Pennsylvania and Maryland. The area of significance is engineering.
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 88000779, listed June 22, 1988. Summary generated October 2026 (model claude-haiku-5-5, prompt v1.1-2026-10-29, confidence medium).
Key facts
| Address | LR 28010 over Conodoguinet Creek, Middle Spring |
|---|---|
| County | Franklin County |
| Listed | June 22, 1988 |
| Reference number | 88000779 |
| Resource type | Structure |
| Period of significance | 1827 |
| Architect / builder | Silas Harry (builder/contractor) |
| Architectural style | Camelback |
| Areas of significance | Engineering |
| Level of significance | State |
| Status (as stated in the nomination) | Altered in 1982; the document describes the appearance as slightly altered. |
| Acreage | 0.9 |
| Coordinates | 40.09818, -77.56961 (NPS GIS) |
What listing means for this property
For a publicly owned building or structure, listing mainly matters when federal funds, permits or licences are involved: projects then go through Section 106 review so effects on the property are considered. Listing also strengthens applications for preservation grants and, for leased income-producing uses, can enable the federal rehabilitation tax credit.
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 88000779.
- Nomination form (PDF, National Archives) — catalog entry
- Wikipedia article (used for cross-checking only; text not reproduced here)
- Wikidata Q6800293
- This listing as JSON
Last updated October 2026. Found an error? See the editorial policy for how to report it.