Ronald Reagan Memorial Tollway

Interstate 88
Route information
Maintained by IDOT and ISTHA
Length:	140.60 mi (226.27 km)
Existed:	July 1987 – present
Major junctions
West end:	I-80 / IL 5 / IL 92 / IL 110 (CKC) in East Moline
	US 30 in Rock Falls I-39 / US 51 in Rochelle I-355 in Downers Grove I-294 in Hillside
East end:	I-290 / I-294 / IL 110 (CKC) in Hillside
Highway system
Interstate Highway System Main Auxiliary Suffixed Business Future Illinois State Highway System Interstate U.S. State Tollways ← IL 84 IL 89 →

Interstate 88 (I-88) is a tolled Interstate Highway in the US state of Illinois that runs from an interchange with I-80 near Silvis and Moline to an interchange with I-290 and I-294 in Hillside, near Chicago. I-88 is 140.60 miles (226.27 km) long. This route is not contiguous to I-88 in New York. Since 2010, all of I-88 has been part of the Chicago–Kansas City Expressway. The highway also runs through the cities of Aurora, Naperville, DeKalb, and Dixon.

Prior to its designation as an Interstate Highway, the route was known as IL 5, and before that, IL 190.

The reason for I-88's original designation and continued existence as an Interstate has to do with a technicality in the old National Maximum Speed Law (NMSL). Originally passed in 1973, NMSL was amended in 1987 to permit 65 mph (105 km/h) speed limits on rural stretches of Interstate Highways only. Even though IL 5 was fully up to Interstate standards, it still had to carry a 55 mph (90 km/h) limit because of this wording in NMSL. The Illinois Department of Transportation (IDOT) and Illinois State Toll Highway Authority (ISTHA) petitioned the American Association of State Highway and Transportation Officials (AASHTO) to re-designate IL 5 as an Interstate, and in 1987, AASHTO approved the request and assigned the Interstate 88 numbering to the highway. NMSL would be completely repealed only eight years later in 1995, but the I-88 shields remain up to this day, even though Illinois 110 shields are being posted throughout the entire Illinois I-88, since it is now part of the Chicago to Kansas City Expressway project, bannered with special "CKC" logos.

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Wikipedia