Where is O’Fallon Illinois? What County is O’Fallon in

O’Fallon is a city in St. Louis County. Clair, Illinois, United States. The city of O’Fallon, is in Illinois IL (St. Clair County), United States. O’Fallon is a city in St. Louis County. Clair, Illinois, United States.

Is O Fallon IL a suburb of St Louis?
Is O Fallon Illinois a good place to live?
What is O Fallon known for?
What county is OFallon IL in?