Allenwood River Bridge
Why it's listed
Built in 1895 by the Groton Bridge and Manufacturing Company of Groton, New York, the Allenwood River Bridge crosses the West Branch Susquehanna River in Northumberland County, Pennsylvania. It consists of five pin-connected through trusses, four of them with eleven panels at 17 feet and one longer main span of 210 feet, for an overall length of 970 feet. The trusses are built from channels, eyebars and lacing bars, and the steel superstructure was supplied by Jones & Laughlin. The piers, abutments and wing walls are coursed ashlar stone masonry. The bridge is regarded as a typical multiple-span Pratt truss and a well-preserved example of a bridge type common in north central Pennsylvania. It also represents the work of a nationally prominent bridge manufacturer. Alterations recorded since construction include a new wing in 1946, a new steel railing in 1954 and a rehabilitation in 1962. The bridge still carries vehicles across the river.
Significance in brief: The nomination describes the bridge as a typical example of a multiple-span Pratt through truss and a well-preserved example of a bridge type frequently used in north central Pennsylvania. It is also cited as work by a nationally prominent bridge manufacturer. 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 88000865, 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 460 over W branch of Susquehanna River, Allenwood |
|---|---|
| County | Northumberland County |
| Listed | June 22, 1988 |
| Reference number | 88000865 |
| Resource type | Structure |
| Period of significance | 1895 |
| Architect / builder | Groton Bridge and Manufacturing Company, Groton, New York (builder/contractor) |
| Architectural style | Pratt through truss |
| Areas of significance | Engineering |
| Level of significance | State |
| Status (as stated in the nomination) | Vehicular use is noted as present; the document lists alterations in 1946 (new wing), 1954 (new steel railing) and 1962 (rehabilitation). |
| Acreage | 0.9 |
| Coordinates | 41.10776, -76.88991 (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 88000865.
- Nomination form (PDF, National Archives) — catalog entry
- Wikipedia article (used for cross-checking only; text not reproduced here)
- Wikidata Q4732084
- This listing as JSON
Last updated October 2026. Found an error? See the editorial policy for how to report it.