O'Fallon is a city in St. Clair County, Illinois, United States. The 2020 census listed the population at 32,289. The city is the second largest city in the Metro East region and Southern Illinois. It sits 5 miles (8.0 km) from Scott Air Force Base and 18 miles (29 km) from Downtown St. Louis.
Midwest
O'Fallon
St. Clair County, IL
Population
32,104
Walk Score
85 · Very Walkable
Median rent
$1,264
Median home value
$260,700
Founded
1854
From Wikipedia. Released under CC BY-SA.
On the National Register
Historic districts
- Scott Field Historic District · listed 1994
Notable landmarks
- Tiedemann House · listed 2020
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