Иллинойс және Миссури штаттарындағы I-72 тас жолы

Interstate Highway in Illinois and Missouri

Interstate 72 (I 72) is an Interstate Highway in the midwestern United States. Its western terminus is in Hannibal, Missouri, at an intersection with U. S. Route 61 (US 61); its eastern terminus is at Country Fair Drive in Champaign, Illinois. The route runs through the major cities of Decatur, Illinois, and Springfield, Illinois. In 2006, the Illinois General Assembly dedicated all of I 72 as Purple Heart Memorial Highway. The stretch between Springfield and Decatur is also called Penny Severns Memorial Expressway, and the section between mile 35 and the Mississippi River is known as the Free Frank McWorter Historic Highway.

The concept of I 72 across Missouri was to create the Chicago–Kansas City Expressway, a rural four lane highway across northern Missouri and west central Illinois from Cameron, Missouri, at I 35 to Springfield, Illinois, at I 55. This would provide a series of rural four lane highways (I 35, US 36, I 72, and I 55) connecting Chicago to the North American Free Trade Agreement (NAFTA) Corridor (High Priority Corridor 23). This would reduce the amount of through traffic, primarily truck traffic, in the St. Louis, Des Moines, and Quad Cities metropolitan areas by serving as an alternate route for I 70 and I 80. The Missouri portion of this route is designated as part of High Priority Corridor 61. Based on the 157 mile (253 km) marker at Route 79, if/when US 36 is upgraded to Interstate standards across Missouri, the future western terminus of I 72 would be at Cameron at the intersection with I 35. Currently, the west end of I 72 route is west of US 61 and flows concurrent with US 36 into Illinois. In 2004, US 36 was upgraded to a four lane expressway between US 61 and US 24 at the Rocket Junction (7 mile (11 km)). There are three exits along this expressway: Veterans Road, Shinn Lane (Hannibal Regional Hospital), and US 24 east at the Rocket Junction. Also, an interchange with Route 15 was installed in Shelbina. Due to funding priorities, upgrading US 36 between Macon and Hannibal was a low priority project and was shelved. The Missouri Department of Transportation (MoDOT) committed to constructing the four lane highway as an at grade expressway only if the five counties served by US 36 east of Macon would contribute half of the $100 million (equivalent to $ in ) cost. Road construction to complete the 52.4 mile (84 km) between Hannibal and Macon began in 2007. In August 2010, the four lane expressway was completed from Macon to Hannibal, completing Missouri's portion of the Chicago–Kansas City Expressway.

Plans exist to extend I 72 westward from its current terminus in Hannibal to St. Joseph, Missouri along the existing US 36, but the proposal was shelved for years despite most of the route being a part of the Chicago–Kansas City Expressway. In May 2023, Missouri lawmakers approved a $2.5 million study on the conversion of US 36 into I 72. The extension of I 72 is seen as a way to relieve the pressure off of I 70 as well as reduce truck traffic in St. Louis. However, in July 2023, the bill was vetoed by Governor Mike Parson who said that it was not the right time to run the study. The extension to I 29 is listed under High Priority Corridor 61B, although part of it was for the CKC and not I 72.

I 72 currently has one auxiliary route, I 172, that serves as a freeway spur for Quincy.