Allegheny County

Allegheny County · dedicated 1982 · County Courthouse, Grant St. between 5th & Forbes Aves., Pittsburgh

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 the World."

TodayHistorical map

Slide toward Today to fade the historical sheet and see the modern map underneath.

Digital Commonwealth, Boston Public Library

Example

under a mile from where William Gabby lived in the 1760s

what this marker records spans 1777 to 1789, overlapping William Gabby's years here

From one family's 77-marker roster

Upload your family tree and TreeAlive finds the markers near where your own ancestors lived.

See your family's markers

Start with a tree file, a FamilySearch sign in, or a WikiTree ID.

Report a problem with this page

The marker isn't at this spotOur pin may be off. If you know where it stands, tell us.I couldn't find the markerWe record what the source recorded. We have not been to look.The sign reads differentlyThat would be an error, and we can pass it to the program.The historical map looks wrongThe period map behind the pin, not the marker itself.Something else

We may pass what you report to the state's marker program. Please don't include personal details.

Marker data: Pennsylvania Historical and Museum Commission via data.pa.gov

More markers nearby

Henry Clay Frick (1848-1919)under 1 mi
Pittsburgh Chinatownunder 1 mi
United Steelworkers of Americaunder 1 mi
Founding of Ironworkers Unionunder 1 mi

On the National Register nearby

Try Street Terminal240 ft
Allegheny County Courthouse and Jail250 ft

Places within about 300 feet of this marker that are listed on the National Register of Historic Places. A nearby listing is not always the marker's own subject.