Interstate 57

Interstate 57 (I-57) is an Interstate Highway in Missouri and Illinois that parallels the old Illinois Central rail line for much of its route. It goes from Sikeston, Missouri, at Interstate 55 to Chicago, Illinois, at Interstate 94. I-57 essentially serves as a shortcut route for travelers headed between the south (Memphis, New Orleans, etc.) and Chicago, bypassing St. Louis, Missouri. Between the junction of I-55 and I-57 in Sikeston, Missouri and the junction of I-55 and I-90/94 in Chicago, I-55 travels for 436 miles (702 km), while the combination of I-57 and I-94 is only 396 miles (637 km) long between the same two points. In fact, both the control cities on the overhead signs, as well as destination mileage signs, reference Memphis along southbound I-57, even as far north as its northern origin at I-94 in Chicago. Likewise, at its southern end, Chicago is the control city listed for I-57 on signs on northbound I-55 south of Sikeston, Missouri, even though I-55 also goes to Chicago.

Interstate 43

Interstate 43 (I-43) is a 191.55-mile-long (308.27 km) Interstate Highway located entirely within the U.S. state of Wisconsin, connecting I-39/I-90 in Beloit with Milwaukee and I-41, U.S. Highway 41 (US 41) and US 141 in Green Bay. Wisconsin Highway 32 (WIS 32) runs concurrently with I-43 in two sections and US 41, US 45, I-94, I-894, US 10, WIS 57, and WIS 42 overlap I-43 once each. There are no auxiliary or business routes connected to I-43; however, as of late 2015 there is a signed alternate route in Milwaukee County.

I-43 came about as a result of toll road proposals that included a Milwaukee to Superior corridor that included Hurley, Wausau and Green Bay. Only the Milwaukee-to-Green Bay section was approved. The route was originally planned to follow an alignment about midway between US 41 and US 141 (the latter paralleled Lake Michigan at the time) along WIS 57. Controversy about this location and use of right-of-way led to the establishment of the current alignment, which follows much of what was the 1950s-era realignment of US 141 from Milwaukee to Sheboygan, and a new alignment from Sheboygan to Green Bay. This section was completed in 1981.