Intersections from west to east:

US40 splits off of I-70 near Pocahontas

IL127 near Greenville

IL140 near Mulberry Grove

I-70 near Vandalia

IL185 joins from the west at Vandalia

US51 joins from the north at Vandalia

IL140 at its eastern end at Vandalia

US51 splits off to head south near Vandalia

IL185 splits off to head east

It passes through these towns: Pocahontas, Smithboro, Vandalia, Bluff City, Brownstown, and St. Elmo.