Illinois River 20 miles (32 km) of its course, the Illinois is separated from the Mississippi River by only about five miles, by a peninsula of land that makes up Calhoun County. The Illinois joins the Mississippi near Grafton, approximately 25 miles (40 km) northwest of downtown St. Louis and about 20 miles upstream from the confluence of the Missouri River and the Mississippi. South of Hennepin, the Illinois River is following the ancient channel of the Mississippi River. The Illinoian Stage, about 300,000 to 132,000 years ago, blocked the Mississippi near Rock Island, diverting it into its present channel. After the
Big Sandy River (Ohio River tributary) It joins the Ohio between Catlettsburg, Kentucky and Kenova, West Virginia, west of Huntington, West Virginia, at the common boundary between West Virginia, Kentucky, and Ohio. The river is navigable and carries commercial shipping, primarily coal mined in the immediate region. The name of the river comes from the presence of extensive sand bars. The Native American names for the river included "Tatteroa", "Chatteroi", and "Chatterwha" which had similar meaning to the English name. It was known to the Lenape as "Sikeacepe", meaning "Salt River", from the presence of salt licks on the river ("see": Licking River). The name "Big