Illinois Route 171
State highway in Will and Cook Counties, Illinois, US
Illinois Route 171 (IL 171) is a 38.61-mile-long (62.14 km) north–south state highway in northeastern Illinois. It runs from U.S. Route 6 (US 6) in Joliet north to Illinois Route 72 at the Chicago–Park Ridge border. The section of IL 171 on Archer Avenue from Joliet to Summit is historically significant, originating as a Native American trail, and later serving for a time as part of the first numbered highway between St. Louis and Chicago.
The current Illinois Route 171 incorporates part or all of previous IL 4, IL 4A, and IL 213.
Route description
IL 171 is mostly two lanes wide from Joliet to Willow Springs, and then four lanes wide to its northern endpoint in Chicago. It is a four-lane freeway for about 2 miles (3.2 km), from its intersection with West 55th Street and Archer Avenue in Summit, to its intersection with West 44th Place in Lyons.
Joliet to Lockport
IL 171 begins in Joliet as Collins Street, at an intersection with US 6 which is East Jackson Street. On its way out of town, it passes the historic Joliet Correctional Center, used as a location in several television shows and movies including The Blues
Brothers. From Joliet to Lockport, it parallels the Des Plaines River, and IL 53 (which had formerly been US 66) on the other side of the river.
“Illinois Route 171” enters the record as state highway in Will and Cook Counties, Illinois, US. Crown Archives preserves that source wording while asking what Illinois, Route and State can confirm, complicate or overturn.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Apr 5, 2026. The linked authority identifier is Q1057527. Authority coordinates are 41.713, -87.911. 2 of 2 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank.
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This entry incorporates text from “Illinois Route 171” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.