St. Louis Metropolitan Area Includes Cities and Counties in Illinois and Missouri
The Greater St. Louis metropolitan area is a bi-state area, which includes the City of St. Louis, which is an independent city, covering parts of Missouri and Illinois. The Mississippi River is the divider between Missouri and Illinois with the Missouri side being more populated than the Illinois side. St Louis city is the second largest metro area in Illinois and the largest metro area in Missouri. For some odd reason, probably political, St. Louis County is independent of the City of St. Louis with populations being calculated separately.
- Bond County, Illinois
- Calhoun County, Illinois
- Clinton County, Illinois
- Jersey County, Illinois
- Macoupin County, Illinois
- Madison County, Illinois
- Monroe County, Illinois
- St. Clair County, Illinois
- Franklin County, Missouri
- Jefferson County, Missouri
- Lincoln County, Missouri
- St Louis City, Missouri
- St Louis County, Missouri
- Warren County, Missouri
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