Illinois Counties
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Illinois Counties

There are one hundred and two counties in Illinois. St. Clair County was the first county established in what is today Illinois. Most counties in Illinois were named after early American leaders, especially of the American Revolutionary War, as well as soldiers from the Battle of Tippecanoe and the War of 1812.

Adams County, Illinois

Adams County Education, Geography, and HistoryAdams County, Illinois Courthouse

Adams County is the westernmost county of the state of Illinois. Based on the 2010 census, the population was 67,103.  Adams County was created on January 13, 1825. The county seat is Quincy. This county is named for John Quincy Adams (1767-1848), sixth President of the United States

Adams County is part of the Quincy, IL-MO Micropolitan Statistical Area.

Etymology - Origin of Adams County Name

The county is named in honor of President John Quincy Adams, Secretary of State under President James Monroe, US Representative and leading defender of free speech.


County QuickFacts: CensusBureau Quick Facts

Adams County History

The County of Adams was formed out of the counties of Pike and Fulton and the attached parts, by an act of the Legislature, approved Jan. 18, 1825, Act: Be it enacted, that all that tract of country within the following boundaries, to-wit: beginning-at the place where the township line between townships three south and four south touches the Mississippi river, thence east on said line to the range line between ranges four and five west, thence north on said range line to the northeast corner of township two north, range five west, thence west on said township line to the Mississippi river, and thence down said river to the place of beginning, shall constitute a county, to be called the county of Adams.

History of Adams County - Information is provided on various topics, including a 62 page book published in 1905

Geography: Land and Water

As reported by the Census Bureau, the county has a total area of 871 square miles (2,257 km2), of which 857 square miles (2,219 km2) is land and 15 square miles (38 km2) (1.68%) is water.

Adams county is located in west Illinois. Part of the Great River National Wildlife Refuge is located in this county.

Neighboring Counties

Bordering counties are as follows:

  • North: Hancock County
  • Northeast: Schuyler County
  • East: Brown County
  • Southeast: Pike County
  • Southwest: Marion County, Mo.
  • Northwest: Lewis County, Mo.


Unified school districts

  • Central Community Unit School District 3
  • Liberty Community Unit School District 2
  • Mendon Community Unit School District 4
  • Payson Community Unit School District 1
  • Quincy Public School District 172

Private schools

  • Blessed Sacrament Catholic School
  • Chaddock School
  • Quincy Christian School
  • Quincy Notre Dame High School
  • St. Dominic Catholic School
  • St. Francis Solanus Catholic School
  • St. James Lutheran School
  • St. Peter Catholic School

Colleges and universities

Blessing-Rieman College of Nursing
John Wood Community College
Quincy University

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