Allegheny County
Pittsburgh, Allegheny County, Pennsylvania
Marker Inscription
ALLEGHENY COUNTY Formed September 24, 1788 out of Westmoreland and Washington counties. Named for the Allegheny River. County seat of Pittsburgh was laid out 1764; became a city in 1816. A center of the iron, steel and other industries and "Workshop of t… transcription continues on the marker
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The Story
When Allegheny County was carved out of Westmoreland and Washington counties in 1788, its seat at Pittsburgh was already a generation old — laid out in 1764 at the strategic forks where the Allegheny and Monongahela join to form the Ohio, a gateway that had drawn soldiers, traders, and settlers pushing west. Incorporated as a city in 1816, Pittsburgh grew into one of the great engines of American industry, its furnaces and mills pouring out the iron and steel that earned the region its "Workshop of the World" reputation. The county's story runs straight from a frontier river junction to the smoke-and-fire heart of the nation's industrial age.
Why it matters
Allegheny County traces the American arc from a contested frontier outpost to an industrial powerhouse whose steel built the country's bridges, railroads, and skylines. It stands as a reminder of how a single river-forks settlement helped forge the modern United States.
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Related events
- · Formation of Allegheny County (1788)
- · Founding of Pittsburgh (1764)
Themes & tags
Nearby & related markers
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