Marion County is a county located in the U.S. state of Illinois. According to the 2020 census, it had a population of 37,729. Its county seat is Salem.
Marion County comprises the Centralia, IL Micropolitan Statistical Area, which is included in... Wikipedia
Population: 36,914 (2022)
County seat: Salem
Area: 576 mi²
Congressional district: 15th
Largest city: Centralia
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