IL 157 is the major north–south road through the busiest towns in Madison County – Collinsville and Edwardsville.

The segment of the highway north from IL 13 to approximately Interstate 270 (I-270) is known as Bluff Road, because it roughly follows the eastern bluffs of the Mississippi River which define the American Bottoms in Madison and St. Clair counties.

It was then extended to the Missouri state line at the Jefferson Barracks Bridge in 1946; this was undone by 1958.

In 1965, the northern terminus was moved to Hamel, replacing U.S. Route 66 Bypass (US 66 Byp.

[2] Media related to Illinois Route 157 at Wikimedia Commons