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Allegheny County
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county in southwestern Pennsylvania, United States
Allegheny County is a county located in southwestern Pennsylvania that includes the city of Pittsburgh and surrounding communities. It is one of Pennsylvania's major population and economic centers, making it significant to the region's development and culture.
AI-generated from the Wikipedia summary — may contain errors.
Research organization · ROR
- Type
- Government
- Founded
- 1788
- Location
- Pittsburgh, United States
- Status
- Active
GRID grid.417890.3 · ISNI 0000 0004 0413 3898
~38 min read
Encyclopedic overview
Allegheny County (/ˌælɪˈɡeɪni/ AL-ig-AY-nee) is a large urban county in Pennsylvania, United States. As of the 2025 census estimate, the population was 1,225,035, a 2% decrease of 25,543 residents since 2020, making it the state's second-most populous county, after Philadelphia County. Its county seat and most populous city is Pittsburgh, Pennsylvania's second most populous city. The county is part of the Greater Pittsburgh region of the commonwealth, and is the center of the Pittsburgh media market.
Allegheny was the first county in Pennsylvania to be given a Native American name. It was named after the Lenape word for the Allegheny River. The meaning of "Allegheny" is uncertain. It is usually said to mean "fine river". Some historians state that the name may come from a Lenape account of an ancient mythical tribe called "Allegewi" who lived along the river before being taken over by the Lenape.
Excerpted from Wikipedia’s “Allegheny County” article, available under the CC BY-SA 4.0 licence.
Gallery (12)
On the map
2 mapped locations