
The O'Fallon Historical Society Museum is housed in the 1904 First National Bank building. The building was also home to the O'Fallon Public Library and the Smiley Brothers Telephone Exchange. The museum focuses on O'Fallon area history including permanent exhibits on native sons, Illustrator Bernie Fuchs and Oscar-winning actor William Holden. Another exhibit explores the St. Ellen coal mine which closed in 1960, but was once an important part of O'Fallon's economy.