| | Description: | Lake County, located in northeastern Illinois, covers an area of 448 square miles and had a 2003 population of 685,019, according to estimates by the U.S. Department of Commerce's Bureau of the Census. Using these figures, Lake County was the 43th largest county in Illinois geographically, but 3rd largest in terms of population. Combining these two measures, Lake County had the 3rd highest population density per square mile among Illinois 102 counties. | |
