Prairie City is a village in McDonough County, Illinois, United States. The population was 407 at the 2020 census. Prairie City is located in the northeast corner of McDonough County at 40°37′15″N 90°27′49″W / 40.62083°N 90.46361°W. It is bordered to the north by Warren County. Illinois Route 41 passes through the village as East Main Street, leadi…Prairie City is a village in McDonough County, Illinois, United States. The population was 407 at the 2020 census. Prairie City is located in the northeast corner of McDonough County at 40°37′15″N 90°27′49″W / 40.62083°N 90.46361°W. It is bordered to the north by Warren County. Illinois Route 41 passes through the village as East Main Street, leading northeast 8 miles to St. Augustine and southwest 6 miles to Bushnell. Macomb, the McDonough county seat, is 21 miles to the southwest.