| Description: | Logan County, located in central Illinois, covers an area of 618 square miles and had a 2003 population of 30,716, according to estimates by the U.S. Department of Commerce's Bureau of the Census. Using these figures, Logan County was the 33rd largest county in Illinois geographically, but 48th largest in terms of population. Combining these two measures, Logan County had the 49th highest population density per square mile among Illinois 102 counties. | |