The Mississippi River forms the western border of Illinois.
Mississippi.
The Mississippi River forms the western border of Illinois.
Mississippi River
Illinois is bordered by the Mississippi River on the west.
Illinois is bordered by the Mississippi River on the west
The Mississippi River
the Mississippi river
The Mississippi River
The Mississippi River forms the wavy western border of Illinois. And the Ohio Wabash River is the southern border of Illinois.
The Mississippi River.
The river that forms the western border of Illinois is the Mississippi River.