| | Description: | Clay County, located in southern Illinois, covers an area of 469 square miles and had a 2003 population of 14,316, according to estimates by the U.S. Department of Commerce's Bureau of the Census. Using these figures, Clay County was the 59th largest county in Illinois geographically, but 22nd smallest in terms of population. Combining these two measures, Clay County had the 22nd lowest population density per square mile among Illinois 102 counties. | |
