The Farmington Valley is located along the western boundary of Hartford County in Connecticut, bordering Litchfield County immediately to the west. It is defined by the Farmington River, which runs through it. Physiographically, the valley is lowlands and floodplain flanked by the Litchfield Hills on the west (which itself is the northern terminus of the larger Mid-Atlantic Highlands Region) and Talcott Mountain on the east (a section of the more extensive Metacomet Ridge).