Adams County, Illinois

Adams County
Adams County Courthouse
Map of Illinois highlighting Adams County
Location within the U.S. state of Illinois
Map of the United States highlighting Illinois
Illinois's location within the U.S.
Coordinates: 39°59′N 91°11′W / 39.99°N 91.19°W / 39.99; -91.19
Country United States
State Illinois
Founded1825
Named forJohn Quincy Adams
SeatQuincy
Largest cityQuincy
Area
 • Total871 sq mi (2,260 km2)
 • Land855 sq mi (2,210 km2)
 • Water16 sq mi (40 km2)  1.9%
Population
 (2020)
 • Total65,737
 • Estimate 
(2023)
64,441 Decrease
 • Density75/sq mi (29/km2)
Time zoneUTC−6 (Central)
 • Summer (DST)UTC−5 (CDT)
Congressional district15th
Websitewww.co.adams.il.us

Adams County is the westernmost county in the U.S. state of Illinois. As of the 2020 census, the population was 65,737.[1] Its county seat is Quincy.[2] Adams County is part of the Quincy, IL–MO Micropolitan Statistical Area.

  1. ^ "State & County QuickFacts". United States Census Bureau. Archived from the original on June 6, 2011. Retrieved July 3, 2014.
  2. ^ "Find a County". National Association of Counties. Archived from the original on May 31, 2011. Retrieved June 7, 2011.