Adams 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 68,277 people, with a population density of about 79.67 persons per square mile.
The county spans a total land area of 857.00 square miles (2,220.00 square kilometers). The administrative center and county seat is Quincy, which often serves as a hub for local governance and services. The largest city within the county by population is Quincy.
Geographically, Adams County experiences varied elevations, with its highest point at Coatsburg 761 ft and its lowest point at Quincy 600 ft. The region operates in the UTC-6.