Mercer's Mill Covered Bridge
Why it's listed
Built in 1880 by B. J. Carter, Mercer's Mill Covered Bridge is a Burr truss span carrying a township road over Octoraro Creek near Christiana. The bridge crosses the line between West Fallowfield Township in Chester County and Sadsbury Township in Lancaster County, and is owned jointly by the two counties. Its end posts are 85 feet long, and it has vertical plank siding along its sides with horizontal siding in the portals. The nomination places it within a thematic group of covered bridges in Lancaster County that show wood frame construction practice in the nineteenth century. Reviewers found the bridge in good condition and considered it a suitable example of the group, though they asked for boundaries that would take in the abutments more fully.
Significance in brief: The nomination treats the bridge as one of a group of nineteenth-century covered bridges in Lancaster County that together illustrate wood frame construction, a theme used for the multiple-resource submission. It is described as being in good condition, with vertical plank siding and horizontal siding in the portals.
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 80003509, listed December 11, 1980. Summary generated October 2026 (model claude-haiku-5-5, prompt v1.1-2026-10-29, confidence medium).
Key facts
| Address | NE of Christiana, Christiana |
|---|---|
| County | Lancaster County |
| Listed | December 11, 1980 |
| Reference number | 80003509 |
| Resource type | Structure |
| Architect / builder | B. J. Carter (builder) |
| Areas of significance | Engineering, Transportation |
| Level of significance | State |
| Status (as stated in the nomination) | Condition described as good |
| Acreage | 0.1 |
| Coordinates | 39.93146, -75.98132 (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 80003509.
- Nomination form (PDF, National Archives) — catalog entry
- Wikipedia article (used for cross-checking only; text not reproduced here)
- Wikidata Q6818245
- This listing as JSON
Last updated October 2026. Found an error? See the editorial policy for how to report it.