page_title: Delaware County, Pennsylvania
hierarchical_section_title: Delaware County, Pennsylvania
context_page_description: Delaware County, colloquially referred to as Delco, is a county located in the U.S. state of Pennsylvania that borders Philadelphia. With a population of 566,747, it is the fifth most populous county in Pennsylvania, and the third smallest in area. The county was created on September 26, 1789, from part of Chester County, and named for the Delaware River.
  Its county seat is Media. Until 1850, Chester was the county seat of Delaware County and, before that, of Chester County.
  Delaware County is adjacent to the city-county of Philadelphia and is included in the Philadelphia–Camden–Wilmington, PA–NJ–DE–MD Metropolitan Statistical Area. Delaware County is the only county covered in its entirety by area codes 610 and 484.
context_section_description: Delaware County, colloquially referred to as Delco, is a county located in the U.S. state of Pennsylvania that borders Philadelphia. With a population of 566,747, it is the fifth most populous county in Pennsylvania, and the third smallest in area. The county was created on September 26, 1789, from part of Chester County, and named for the Delaware River.
  Its county seat is Media. Until 1850, Chester was the county seat of Delaware County and, before that, of Chester County.
  Delaware County is adjacent to the city-county of Philadelphia and is included in the Philadelphia–Camden–Wilmington, PA–NJ–DE–MD Metropolitan Statistical Area. Delaware County is the only county covered in its entirety by area codes 610 and 484.
caption: Location within the U.S. state of Pennsylvania