Illinois state highway system Illinois Tollway system

Interstate 180 (abbreviated I-180) is a north–south spur highway that runs from Princeton, Illinois to the small town of Hennepin, Illinois on its southern terminus. It is 13.19 miles (21.23 km) long.

Interstate 180 winds through a forested, hilly area in north-central Illinois. The local topography surrounding I-180 is heavily influenced by the Illinois River. It has four lanes for its entire length.

Construction of I-180 was completed in 1969. The freeway was built primarily to connect Interstate 80 to a new Jones & Laughlin steel plant built in 1965 at Hennepin, IL. However, the steel plant closed soon after I-180 was built, and did not re-open until August 2002. I-180 is one of the least traveled interstates in the nation, serving 2,450 – 4,100 vehicles per day as of 2007.

The Illinois Department of Transportation does not provide exit numbers for any exits on I-180.