Carrie Blast Furnace Number 6 and 7
Why it's listed
Carrie Blast Furnaces Numbers 6 and 7 are two steel-frame iron-producing stacks on the north bank of the Monongahela River, a short distance east of Pittsburgh, in the boroughs of Rankin, Munhall and Swissvale. Built in 1906-1907, they formed part of the integrated Carrie plant that supplied basic iron to the open-hearth furnaces of the Homestead Steel Works from 1907 to 1978. The furnaces operated as a pair, sharing ore storage, hot blast stoves, blowing engines and gas-processing equipment. Their gas was cleaned and used to fire boilers and generate electricity for the mill. Most of the original equipment dates from the 1920s to the 1940s, a level of integrity uncommon among furnaces built before World War I. The district also includes the Hot Metal Bridge, built in 1900-1901, which carried molten iron across the river. The property is significant for its engineering and its role in industrial production.
Significance in brief: The nomination argues the furnaces are the only remaining pre-World War II blast furnaces in the Pittsburgh District and among few in the United States that retain much of their original equipment. It states they are exceptional examples of integrated 'Northern' or 'Mesabi' practice ironmaking, and that their technology and role in the industrial economy make them nationally significant in engineering and industry.
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 06001070, listed September 20, 2006. Summary generated October 2026 (model claude-haiku-5-5, prompt v1.1-2026-10-29, confidence medium).
Key facts
| Address | North side of Monongahela River .5 mi west of Rankin Bridge, Rankin, Munhall, Swissvale boroughs |
|---|---|
| County | Allegheny County |
| Listed | September 20, 2006 |
| Reference number | 06001070 |
| Resource type | District |
| Period of significance | 1906-1941 |
| Architectural style | No Style |
| Criteria |
|
| Level of significance | National |
| National Historic Landmark | Yes, designated September 20, 2006 |
| Status (as stated in the nomination) | Carrie 6 and 7 remain standing as a district of twenty-seven resources; the rest of the Carrie plant has been torn down and access to the site was limited during study. |
| Coordinates | 40.41387, -79.88973 (NPS GIS) |
What listing means for this property
This is a historic district. Buildings within its boundary are either contributing (they add to the district's significance) or non-contributing. Owners of contributing income-producing buildings can claim the 20% federal rehabilitation tax credit; homeowners should look at state credits. National Register districts impose no design review by themselves; a local historic district ordinance, if one exists, does (the difference explained).
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 06001070.
- Nomination form (PDF, National Archives) — catalog entry
- Wikipedia article (used for cross-checking only; text not reproduced here)
- Wikidata Q5046232
- This listing as JSON
Last updated October 2026. Found an error? See the editorial policy for how to report it.