Interstate 172 (I-172) is a spur route from Interstate 72. The highway runs north from its start outside of Hannibal, Missouri to about 2.5 miles (4 km) west of Fowler, Illinois. At U.S. Highway 24, Interstate 172 becomes Illinois Route 336, which runs north and east to Macomb, Illinois via Carthage, Illinois. The entire portion of I-172 and I-72 from I-172 east to Springfield is also known by its former name, the Central Illinois Expressway. I-172 is 19.69 miles (31.69 km) long.
I-172 highlighted in red
|Auxiliary route of I-72|
|Maintained by IDOT|
|Length||19.69 mi (31.69 km)|
I-172 begins at a trumpet interchange with I-72/US 36, about 5 miles (8.0 km) east of Hannibal, MO, before immediately entering Adams County. I-172 enters the Quincy area at exit 10 (IL 96), passing to the far east of the city. I-172 ends just northeast of Quincy, ending at US 24, continuing north as IL 110/IL 336 (Chicago–Kansas City Expressway).
Interstate 172 originally was what Interstate 72 is now from Springfield, Illinois to the current interchange with I-172. This was approved by the American Association of State Highway and Transportation Officials (AASHTO) on June 9, 1991.
On April 23, 1995, after a re-examination by the Federal Highway Administration, the highway to Hannibal was re-designated I-72, with the highway north to Quincy, Illinois redesignated as Interstate 172. The highway is non-chargeable, meaning that even though it is an Interstate (designed and constructed to Interstate Highway standards and specifications), it was not built with federal funds.
After Interstate 172 was completed, the Illinois Department of Transportation continued development of the four-lane highway as Illinois Route 336. Construction is ongoing (2013) the 4-lane highway is complete to a terminus interchange with U.S. 136 just west of Macomb, Illinois. In 2013, grading and earth work has begun on a Macomb bypass. This construction is expected to take 4 years to complete, due to state funding and bridge construction required over the east branch of the LaMoine River.
|Pike||Levee Township||0.00||0.00||0||Southbound exit and northbound entrance; southern terminus, exit 0 is for 72 west; I-72 east exit 4, west exit 4A|
|Adams||Fall Creek Township||3.18||5.12||2|
|Quincy||14.47||23.29||14||Serves Quincy Airport|
|Ellington Township||15.90||25.59||15||Columbus Road, Wismann Lane|
|Continuation beyond US 24|
|1.000 mi = 1.609 km; 1.000 km = 0.621 mi|
- Illinois Technology Transfer Center (2007). "T2 GIS Data". Retrieved 2007-11-08.
- Schoenburg, Bernard (1995-04-28). "Road to the top? Designation puts expressway in the 'big leagues'". The State Journal-Register (Springfield, IL).
- Kurumi. Interstate x72. Last updated November 20, 2005. Retrieved May 14, 2006.