The
Great Valley is a west-to-east
valley through the center of
Chester County, Pennsylvania,
USA. It is also sometimes referred to as Chester Valley, and both names are in use throughout the region. The valley stretches from the
Schuylkill River in
Montgomery County in the east, southwesterly through Chester and
Lancaster counties. The valley is most distinct in central Chester County, although traces of it can be followed almost the entire distance between the
Delaware and
Susquehanna rivers.