Greater Pittsburgh is a populous region centered around Pittsburgh, Pennsylvania, the region's largest city and economic hub. The region encompasses Pittsburgh's urban core county, Allegheny, and six adjacent Pennsylvania counties: Armstrong, Beaver, Butler, Fayette, Washington, and Westmoreland in Western Pennsylvania, which constitutes the Pittsburgh, PA Metropolitan Statistical Area MSA as defined by the U.S. Census Bureau. As of the 2020 census, the Greater Pittsburgh region had a population of over 2.37 million people. Roughly one-fifth of the entire population of Pennsylvania resides within the region.[citation needed] The core city, Pittsburgh, has a population of 302,971, making it the second-largest city in the state. Over half of the region's population resides within Allegheny County, which has a population of 1.24 million and is the second-largest county by population in the state.
