Jo Daviess County is a county located in the U.S. state of Illinois. As of the most recent data available, the county has a population of approximately 22,289 people, with a population density of about 37.09 persons per square mile.
The county spans a total land area of 601.00 square miles (1,557.00 square kilometers). The administrative center and county seat is Galena, which often serves as a hub for local governance and services. The largest city within the county by population is Galena.
Geographically, Jo Daviess County experiences varied elevations, with its highest point at Warren 1,012 ft and its lowest point at East Dubuque 610 ft. The region operates in the UTC-6.