Duval -- U.S. County in Florida Population (2000): 778879 Housing Units (2000): 329778 Land area (2000): 773.667651 sq. miles (2003.789932 sq. km) Water area (2000): 144.569810 sq. miles (374.434073 sq. km) Total area (2000): 918.237461 sq. miles (2378.224005 sq. km) Located within: Florida (FL), FIPS 12 Location: 30.320873 N, 81.638873 W Headwords: Duval Duval, FL Duval County Duval County, FL