Interstate 90 in Illinois

The 76-mile (122 km) Northwest Tollway portion of I-90 opened on August 20, 1958.[3] Prior to the opening, the first vehicle to officially travel the new roadway was a covered wagon navigated by local resident John Madsen who took 5 days to make the journey.[4]

On September 7, 2007, highway officials responding to an effort by state lawmakers renamed the Northwest Tollway to Jane Addams Memorial Tollway, after Jane Addams, the Nobel Peace Prize winner and founder of the Settlement House movement in the United States.[5][6]

The Illinois Tollway's 2005–2012 Congestion-Relief Program provided $644.1 million in improvements to the I-90 corridor.[7] Projects included rebuilding and widening of the tollway between I-39 and Rockton Road, including a reconfiguration of the I-90/I-39 interchange to improve traffic flow. This construction started in 2008 and was completed by the end of 2009.[8]

From 2013 to 2016, over $2 billion was spent on rebuilding and widening the Jane Addams Memorial Tollway from I-39 to the Kennedy Expressway. The inside shoulders were widened for future transit opportunities, and active traffic management was incorporated into the corridor from IL 59 to the eastern end.[9][10] In addition, almost all of the crossroad bridges were rebuilt and several interchanges were reconfigured/expanded.[11] In 2019, a $33.4 million interchange with IL 23 was added near Marengo to provide the first I-90 interchange in McHenry County.[12]

Until 1978, I-90 was routed on the Congress Street Expressway (later named the Eisenhower Expressway) which was extended from the Loop to the intersection of the Northwest Tollway and IL 53. The Kennedy Expressway was signed only as I-94, and the portion of present-day I-90 between the Edens Expressway and IL 53 was not signed as an Interstate Highway. This provided a non-toll section of I-90 between downtown Chicago and IL 53. The route designations were changed to their present form when I-90 was moved to follow the entire length of the Kennedy Expressway and the Jane Addams Tollway, and the original route was designated I-290.

Chicago Skyway in 1999

The Chicago Skyway was originally known as the Calumet Skyway.[13] It cost $101 million (1958, $791 million in 2011) to construct and took about 34 months (nearly 3 years) to build. Nearly 8 miles (13 km) of elevated roadway, the Chicago Skyway was originally built as a shortcut from State Street, a major north-south street on Chicago's South Side that serves the Loop, to the steel mills on the Southeast to the Indiana state line where the Indiana Toll Road begins. Later, when the Dan Ryan Expressway opened, the Chicago Skyway was extended west to connect to it. There are only two eastbound exits east of the toll barrier, whereas there are four westbound exits west of the toll barrier (so that no exits are available until one has crossed the bridge and paid the toll). The Chicago Skyway opened to traffic on April 16, 1958.[13][14]

The Skyway's official name, referring to it as a "toll bridge" rather than a "toll road", is the result of a legal quirk. At the time of its construction, the city charter of Chicago did not provide the authority to construct a toll road. However, the city could build toll bridges, and it was found that there was no limit to the length of the approaches to the bridge. Therefore, the Skyway is technically a toll bridge spanning the Calumet River with a six-mile-long (9.7 km) approach. This also is part of the reason that there are no exits available until after one has crossed the bridge and paid the toll.[15]

Historically, the Chicago Skyway was signed as, and was widely considered to be part of, I-90 from the mid-1960s forward (after I-90 in this area had been swapped with I-94). However, around 1999, the City of Chicago realized they had never received official approval to designate the Skyway as I-90. The city subsequently replaced most of the "I-90" signage with "TO I-90/I-94" signage. However, the Illinois Department of Transportation (IDOT) has always and continues to report the Skyway as part of the Interstate Highway System, and the Federal Highway Administration also considers the Chicago Skyway an official part of I-90.[16]

In the 1960s, the newly constructed Dan Ryan Expressway and the neighboring Calumet Expressway, Kingery Expressway and Borman Expressway provided free alternatives to the tollway, and the Skyway became much less used. As a result, from the 1970s through the early 1990s, the Skyway was unable to repay revenue bonds used in its construction.[17] Traffic volumes rebounded from the late 1990s onward, partially because of the construction of casinos in Northwest Indiana, along with reconstruction of the Dan Ryan, Kingery and Borman Expressways.[18] In June 2005, the Skyway became compatible with electronic toll collection, with users now able to pay tolls using I-PASS or E-ZPass transponders.[19]

Chicago's Department of Streets and Sanitation formerly maintained the Chicago Skyway Toll Bridge System. A transaction that gave the city a $1.83 billion cash infusion leased the Skyway to the Skyway Concession Company, a joint-venture between the Australian Macquarie Infrastructure Group and Spanish Cintra Concesiones de Infraestructuras de Transporte S.A., which assumed operations on the Skyway on a 99-year operating lease. The agreement between SCC and the city of Chicago marked the first time an existing toll road was moved from public to private operation in the United States.[20]