Before automobiles The route followed by IL 171 from Joliet to Summit was originally a Native American trail. It can be found on a map from 1837. This original trail continued northeast beyond Summit around the southern shore of historic Mud Lake as a dry land route past the marshy
Chicago Portage, ending where Downtown Chicago is now. This ancient trail is known today as
Archer Avenue.
Original S.B.I. 171 Illinois State Bond Issue Route 171 (S.B.I. 171) was established in 1924 in the northwestern part of the state, and ran from
Thomson to
S.B.I. 78, along what is now called the Argo-Fay Route. This first IL 171 appeared on maps starting in 1929, but was gone by 1931 and never reappeared on this alignment.
Original S.B.I. 4 The first road from Joliet to Chicago was shown as "Lone Star Route" on early road maps. In 1924 S.B.I. 4 was designated as the first numbered route from
Saint Louis to
Chicago. From Joliet to Lyons, the original S.B.I 4 followed the route of modern IL 171, along
Archer Avenue, except for a jog through Lemont on State and Main streets to bypass an unpaved section of Archer Avenue. It then rejoined Archer Avenue at Sag Bridge. By 1932, Archer Avenue was completely paved, so IL 4A no longer detoured through Lemont. In 1934, IL 4A was extended east into Chicago along 55th Street and Garfield Boulevard to South Park Boulevard (now called
Martin Luther King Jr. Drive), where it turned north to end at Leif Erickson Drive (now called
Lake Shore Drive), which was US 12/US 20/
US 41 at the time. This 1934 endpoint was roughly at the site of today's
McCormick Place. The next year, the 1935 map shows that the section of former IL 4A from Summit to Lyons had been designated as IL 213. It also shows IL 4A truncated to the intersection of Garfield Boulevard and South Park Boulevard, which had been designated
US 330. By 1939 IL 4A had been rerouted from 55th Street, more directly into Downtown Chicago on Archer Avenue. In 1935, IL 4, IL 4A's parent route, was truncated to end at Springfield, having been replaced by US 66 from Springfield to Chicago. This left IL 4A from Joliet to Chicago as an odd remote orphan of its Downstate parent route until it was eliminated in 1967.
Modern Route 171 In 1946, IL 213 was renumbered IL 171, still connecting IL 4A in Summit to US 34 in Lyons. This is the first appearance of the modern IL 171. In the mid-1960s, as part of the construction of the new
Stevenson Expressway, IL 171 was upgraded to a freeway between Summit and Lyons, including its interchange with I-55. In 1967, IL 4A was eliminated, and its section between Joliet and Summit became a southern extension of IL 171. In 1998, IL 171 was extended northward through several suburban communities and the Northwest Side of Chicago, crossing I-290 and I-90, to end at IL 72 (Higgins Road) on the border between Chicago and
Park Ridge near
O'Hare Airport.
Claims of supernatural occurrences The section of IL 171 on Archer Avenue between Sag Bridge and Justice is reputed to be haunted. There have been reports of ghostly monks in the cemetery at
St. James at Sag Bridge Church since the mid-1800s; in 1977 police are said to have chased a group of them into the cemetery. A
vanishing hitchhiker known as
Resurrection Mary is said to ask for rides between the
Willowbrook Ballroom in Willow Springs and Resurrection Cemetery in Justice - and then disappear into the cemetery. ==Major intersections==