Chester is a city in Delaware County, Pennsylvania, United States within the Philadelphia Metropolitan Area. It is the only city in Delaware County and had a population of 33,972 as of the 2010 census.
Incorporated in 1682, Chester is the oldest city in Pennsylvania and is located on the western bank of the Delaware River between the cities of Philadelphia and Wilmington, Delaware. It was the location of William Penn's first arrival in the Province of Pennsylvania and the county seat for Chester County from 1682 to 1788 and Delaware County from 1789 to 1851.
Chester evolved over the centuries from a small town with wooden shipbuilding and textile factories into an industrial powerhouse producing steel ships for two World Wars and a myriad of consumer goods. Since the mid-twentieth century, it has lost its manufacturing base and over half of its residents and devolved into a post-industrial city struggling with pollution, poverty and crime.