The entire highway in Illinois is named the Walter Payton Memorial Highway after Pro Football Hall of Famer Walter Payton, who wore #34 for the Chicago Bears.

After leaving Iowa via the Great River Bridge, US 34 enters Gulfport.

At a 5-ramp parclo, US 34 turns north onto a 4-lane divided expressway (signed as US 67/IL 110 (CKC)).

[3] In the middle of Coldbrook and Cameron, the two routes meet a local road at a diamond interchange.

At another cloverleaf interchange, IL 110 diverges north via I-74 while US 34 moves eastward (soon northeastward).

In Princeton, it then follows IL 26 before it reaches Elm Place where US 34 branches off east (soon northeast).

Near the Illinois Tollway headquarters, it meets I-355, as well as I-88, at a mix of interchanges.

At that point, the road continues on as Ogden Avenue and Historic US 66 all the way to Chicago.

[5][6] US 34 formerly overlapped US 66 all the way to its endpoint in downtown Chicago, but was truncated to its intersection with US 66 and IL 43 in Berwyn in 1970.

[7] When US 66 was subsequently eliminated, the endpoint of US 34 was left at that location—the intersection of Ogden and Harlem Avenues in Berwyn.

[8] With the re-signing of much of Historic US 66, the history of US 34's eastern endpoint is becoming much more clear.