Clay -- U.S. County in Tennessee Population (2000): 7976 Housing Units (2000): 3959 Land area (2000): 236.109850 sq. miles (611.521677 sq. km) Water area (2000): 23.143592 sq. miles (59.941625 sq. km) Total area (2000): 259.253442 sq. miles (671.463302 sq. km) Located within: Tennessee (TN), FIPS 47 Location: 36.564515 N, 85.548616 W Headwords: Clay Clay, TN Clay County Clay County, TN