| Adams County Illinois Cities/Towns - Camp Point, Clayton, Coatsburg, Columbus, Golden, La Prairie, Liberty, Lima, Loraine, Mendon, Payson, Plainville, Quincy (County Seat), Ursa |
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Your Ad Here Adams County is a county located in the U.S. state of Illinois. As of the 2000 census, the population was 68,277. Its county seat is Quincy, Illinois. History The County was formed in 1825. Its name is in honor of the sixth President of the United States, John Quincy Adams. ![]() |