The Naugatuck River Valley refers to the watershed area of the Naugatuck River in the western part of Connecticut. The Naugatuck Valley straddles parts of Litchfield County, New Haven, and Fairfield counties. The Route 8 corridor and Waterbury Branch of the Metro-North railroad line run along the river valley. Geographically, it comprises the municipalities located within the Naugatuck River basin. During the 19th and 20th centuries, the area was one of the main manufacturing centers in New England, and most of the communities around the river were emblematic New England mill towns.