Interstate 180
I-180 highlighted in red
Route information
Auxiliary route of I-80
Maintained by IDOT
Length	13.19 mi[1] (21.23 km)
Existed	1967–present
History	Completed in 1969[2]
NHS	Entire route
Major junctions
South end	IL 26 / IL 71 in Hennepin
Major intersections	US 6 in Princeton
North end	I-80 in Princeton
Location
Country	United States
State	Illinois
Counties	Putnam, Bureau
Highway system
Interstate Highway System Main Auxiliary Suffixed Business Future Illinois State Highway System Interstate US State Tollways Scenic
← IL 179 → IL 180

Interstate 180 (I-180) is a north–south spur highway in Illinois that runs from Princeton to the small town of Hennepin at its southern terminus. It is 13.19 miles (21.23 km) long.^[1]

Route description

I-180 begins as a continuation of Illinois Route 71 (IL 71) at a diamond interchange with IL 26 northeast of Hennepin. The interchange is located adjacent to a former steel mill that was most recently operated by ArcelorMittal but closed in 2009 and demolished in 2017.^[3] The freeway travels northwest, carrying I-180 and IL 26 in a concurrency, and crosses the Illinois River on the north side of Hennepin to enter Bureau County.^[4]

On the west side of the river, IL 26 separates from I-180 and the freeway crosses over IL 29 before splitting at a Y interchange. I-180 turns north, intersecting an expressway that connects to IL 29, and travels northeast across Big Bureau Creek to intersect IL 26. The freeway intersects US Route 6 (US 6) east of Princeton and continues due north to its terminus, a trumpet interchange with I-80. I-180 has four lanes for most of its length, though an additional 1.5-mile (2.4 km) southbound lane exists prior to the IL 29 exit.^[4]

History

Construction of I-180 was completed in 1969.^[2] The freeway was built primarily to connect I-80 to a new Jones and Laughlin Steel Company steel plant built in 1965 in Hennepin.^[5] However, the steel plant closed soon after I-180 was built and did not reopen until August 2002.^{[citation needed]} Federal auditors criticized its construction and called it a political favor that was put ahead of requests from Tucson, Arizona, and Tacoma, Washington.^[6]

I-180 is one of the least traveled Interstates in the nation, serving 1,950–3,600 vehicles per day as of 2013^[update].^[7]

In the 2010s, work started to reconstruct portions of the bridge carrying I-180 over the Illinois River. A three-year project to rebuild the deck began in 2020.^[8]

Exit list

County	Location	mi[4]	km	Exit	Destinations	Notes
Putnam	Hennepin	0.00	0.00	14	IL 26 – Hennepin, Lacon IL 71 east	Southern end of IL 26 concurrency; roadway continues as IL 71
Illinois River		1.0	1.6	Gudmund "Sonny" Jessen Bridge
Bureau	Bureau Junction	2.5	4.0	12	IL 26 north – Bureau Junction	Northern end of IL 26 concurrency; northbound exit and southbound entrance
		3.5	5.6	—	To IL 29 south – Peoria	Access via unnamed connector expressway
		8.0	12.9	7	IL 26 – Princeton
	Princeton	12.0	19.3	3	US 6 (Grand Army of the Republic Highway) – Princeton, Spring Valley
		13.2	21.2	—	I-80 – Davenport, Joliet	Northern terminus; I-80 exit 61
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Concurrency terminus