Pittsburgh
Second-most populous city in Pennsylvania, U.S.

Pittsburgh is a city in Allegheny County, Pennsylvania, United States, and its county seat. Located in southwestern Pennsylvania where the Allegheny and Monongahela Rivers meet to form the Ohio River, it had a population of 302,971 at the 2020 census, making it the second-most populous city in Pennsylvania after Philadelphia. The Pittsburgh metropolitan area has over 2.43 million people, making it the largest in the Ohio Valley and Appalachia, the second-largest in Pennsylvania, and the 28th-largest in the U.S. The greater Pittsburgh–Weirton–Steubenville combined statistical area includes parts of Ohio and West Virginia.
This brief starts where responsible research should: with the source description of “Pittsburgh” as second-most populous city in Pennsylvania, U.S. Everything that follows is an evidence route, not borrowed authority.
Why this record matters
The subject matters to the places & architecture register because the source frames it as second-most populous city in Pennsylvania, U.S. Its deeper value depends on whether names, dates, institutions and citations support that framing.
Maps, plans, fabric surveys and administrative records can establish how the site’s name, extent and function changed over time. The source revision retrieved here is dated Sep 18, 2026. The first chronological checks are 2020.
A single description cannot reconcile every naming convention, rebuilding phase or administrative transfer associated with a place. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Treat names, boundaries and functions as historically changeable. Maps, plans, inventories and administrative records can clarify what the place meant at different dates.
- Historic place names
- Jurisdictional context
- Routes into maps and plans
Contemporary maps, plans, listed-building records, estate papers and the responsible local or national archive.
Three-step research path
- Establish the record: confirm the title “Pittsburgh”, its source revision and the description used here.
- Expand the search: follow Pittsburgh primary sources, Pittsburgh archive and Pittsburgh research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Pittsburgh”?
- Which authority defined the place, boundary or structure at the relevant date?
- What physical evidence or contemporary plan supports the description?
Search terms from this dossier
This entry incorporates text from “Pittsburgh” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.