Interstate 90 in Illinois - Route Description

Route Description

Interstate 90 enters from Wisconsin with Interstate 39. At the U.S. Route 51 exit, I-39/90 becomes the Jane Addams Memorial Tollway. The two Interstates run south to Rockford, where I-39 continues south (as a freeway) to La Salle/Peru. I-90 continues southeast along the tollway through the Chicago area. In Schaumburg, I-90 meets the western end of Interstate 290, the only loop from I-90 in Illinois.

I-90 passes O'Hare International Airport, where Interstate 190, the only spur of I-90 in Illinois, branches west to the airport terminals. I-90 continues southeast as the Kennedy Expressway (a freeway) and is later joined with eastbound Interstate 94 - westbound I-94 runs on the Edens Expressway. I-90/94 then passes through the city, intersecting the eastern end of I-290 just west of the Chicago Loop. South of I-290, the highway is given the name of the Dan Ryan Expressway.

In Chicago's South Side, I-90 splits off from I-94 and becomes the Chicago Skyway, again becoming a toll road. I-90 then runs directly southeast to the Indiana state line, and becomes the Indiana Toll Road at the state line.

Often confusing to non-residents is the direction system for I-90/94, in which signs that say "I-90/94 West" go north/northwest and signs that say "I-90/94 East" go south/southeast. This naming system is due to the overall direction of the expressway. I-90/94 West goes north, splits into I-94 and I-90, continues north to Wisconsin, and then goes west, I-90 going to Seattle. I-90/94 East goes south, splitting into two pieces, and then turns northeast, I-90 ending in Boston.

There is some dispute as to whether the Chicago Skyway is an official part of the Interstate Highway System. The city of Chicago replaced many I-90 shields to "TO I-90" when it determined that the city may have never applied for Interstate designation for the skyway. However, the Federal Highway Administration considers the Skyway as being part of I-90, and the Illinois DOT has always and continues to report it as such. See List of gaps in Interstate Highways for more information.

Up until late 2007, the interstate was known as the "Northwest Tollway" between O'Hare Int'l to Rockford. Since late 2007, it is now known as the "Jane Addams Memorial Tollway", although many locals still refer to the road by its original name.