Lock Ridge Furnance Complex
Also known as: Lock Ridge Furnace Museum
The pin is a point inside the NPS boundary polygon, not a surveyed location.
Why it's listed
Alburtis, in Lehigh County, Pennsylvania, holds the remains of an anthracite iron works built in 1868 by the Thomas Iron Company. Furnace No. 7 is a square stone base about thirty feet high, topped by a brick cone, and it sits beside an engine room, a cast room and a weighmaster's house. The works used anthracite coal, a hot blast and a steam engine, a process that replaced charcoal and water-powered bellows and that helped drive the iron industry of the Lehigh Valley. The Thomas Iron Company operated the furnaces until December 1921, after which the metal was sold for scrap and the stone buildings were left to decay. Lehigh County acquired the ruins for a park and museum in the early 1970s, and restoration work was completed in 1975. The site is significant for its link to the industrial change that supplied iron for the country's railroads and machinery.
Significance in brief: The nomination argues the complex illustrates the nineteenth-century shift to anthracite-fueled, hot-blast iron making that drove the anthracite iron industry of the Lehigh Valley. Furnace No. 7 was built in 1868 by the Thomas Iron Co., which kept it operating until 1921. The document also states that it is the only remaining group of structures from the furnaces operating in 1876 in central and eastern Pennsylvania, apart from a Scranton museum site.
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 81000547, listed September 11, 1981. Summary generated October 2026 (model claude-haiku-5-5, prompt v1.1-2026-10-29, confidence medium).
Key facts
| Address | Franklin and Church Sts., Alburtis |
|---|---|
| County | Lehigh County |
| Listed | September 11, 1981 |
| Reference number | 81000547 |
| Resource type | Building |
| Period of significance | 1800-1899 |
| Architectural style | Pennsylvania vernacular (weighmaster's house); Victorian Gothic lines (complex, as described) |
| Areas of significance | Industry |
| Level of significance | Local |
| Status (as stated in the nomination) | Converted into a museum and park by Lehigh County in the 1970s after restoration work completed in 1975 |
| Acreage | 6 |
| Coordinates | 40.50881, -75.59383 (NPS GIS) |
What listing means for this property
National Register listing is honorary: it recognises significance and does not restrict what a private owner may do without federal money or permits. It unlocks the 20% federal rehabilitation tax credit for income-producing buildings, state credits in many states, and Section 106 review when federal agencies are involved. See what listing means in practice.
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 81000547.
- Nomination form (PDF, National Archives) — catalog entry
- Wikipedia article (used for cross-checking only; text not reproduced here)
- Wikidata Q139744519
- This listing as JSON
Last updated October 2026. Found an error? See the editorial policy for how to report it.