Illinois Route 23

Illinois Route 23
IL 23 highlighted in red
Route information
Maintained by IDOT
Length	122.77 mi[2] (197.58 km)
Existed	November 5, 1918[1]–present
Major junctions
South end	IL 116 in Pontiac
Major intersections	I-55 in Pontiac US 6 / IL 71 in Ottawa I-80 in Ottawa US 52 in Serena US 34 in Leland US 30 in Waterman I-90 Toll near Marengo US 20 in Marengo
North end	US 14 in Harvard
Location
Counties	Livingston, LaSalle, DeKalb, McHenry
Highway system
Illinois State Highway System Interstate US State Tollways
← IL 22 → I-24

Illinois Route 23 (IL 23) is a north–south state highway in northern Illinois. It runs from Illinois Route 116 in Pontiac north to U.S. Route 14 south of Harvard. This is a distance of 122.77 miles (197.58 km).^[2]

Illinois 23 was established in 1918 as one of the original 46 SBI routes. The routing of Illinois 23 has not changed since its establishment.

Route description[]

Illinois 23 is a major arterial route in rural central and north-central Illinois. It is a parallel to the Interstate 39/U.S. Route 51 combination approximately 20 miles (32 km) to the west.

The road starts near downtown Pontiac and runs as the main highway north, intersecting with Interstate 55 and former U.S. Route 66. From this point, Illinois 23 continues as a 2-lane highway, turning west and running through Cornell. After that, it turns back north to travel through the middle of Streator, where the route splits to follow two different one-way streets (Park Street and Bloomington Street). Route 23 continues through Grand Ridge to Ottawa, where the road follows 1st Ave and State street, to form a concurrent with Illinois Route 71—Illinois 71 across the Illinois River. The highway once again splits into two one-way streets (Columbus and LaSalle Streets) through downtown Ottawa, until a block south of its junction with U.S. Route 6, where Illinois 71 departs toward the east.

North of Ottawa, Illinois 23 has a full diamond interchange with Interstate 80. Illinois 23 has two additional concurrencies with U.S. Route 34 and U.S. Route 52, though no notable cities are present between Ottawa and DeKalb. Illinois 23 runs under Interstate 88 with no interchange, though access is available via Fairview Drive to two parallel roads with interchanges (Peace Road and Annie Glidden Road). Between DeKalb and Sycamore, Illinois 23 has four lanes. In Sycamore, Illinois 23 briefly overlaps Illinois Route 64. After one final concurrency at Illinois Route 72 near Genoa, Illinois 23 has an interchange with Interstate 90. It intersects U.S. Route 20 and the western terminus of Illinois Route 176 in Marengo, and terminates south of Harvard at U.S. Route 14.

Major intersections[]

County	Location	mi[3]	km	Destinations	Notes
Livingston	Pontiac	0.00	0.00	IL 116 (Howard Street) / Historic US 66 south	South end of Historic US 66 overlap
		0.4	0.64	Historic US 66 north	North end of Historic US 66 overlap
	​	2.6	4.2	I-55 – Joliet, Bloomington	I-55 exit 201
	​	7.4	11.9	IL 170 north
	​	21.9	35.2	IL 17
La Salle	Streator	26.0	41.8	IL 18 (Bridge Street, Main Street)
	Ottawa	41.3	66.5	IL 71 west (Hitt Street)	South end of IL 71 overlap
		41.4	66.6	Ottawa Bridge over the Illinois River
		42.4	68.2	US 6 / IL 71 east (Norris Drive)	North end of IL 71 overlap
		43.9	70.7	I-80 – Joliet, Moline, Rock Island	I-80 exit 90
	​	50.4	81.1	US 52 west (North 37th Road)	South end of US 52 overlap
	​	52.4	84.3	US 52 east (North 38th Road)	North end of US 52 overlap
	​	59.5	95.8	US 34 west (Walter Payton Memorial Highway)	South end of US 34 overlap
	​	63.6	102.4	US 34 east (Walter Payton Memorial Highway)	North end of US 34 overlap
DeKalb	Waterman	74.3	119.6	US 30 (Lincoln Street)
	DeKalb	85.4	137.4	IL 38 (Lincoln Highway)
	Sycamore	90.8	146.1	IL 64 west (State Street)	South end of IL 64 overlap
		91.4	147.1	IL 64 east (State Street)	North end of IL 64 overlap
	Genoa	98.9	159.2	IL 72 west (Main Street)	South end of IL 72 overlap
	​	100.9	162.4	IL 72 east	North end of IL 72 overlap
McHenry	​	107.2	172.5	I-90 Toll (Jane Addams Memorial Tollway) – Chicago, Rockford	I-Pass only; I-90 exit 36
	Marengo	112.2	180.6	US 20 (General Grant Highway)
		112.7	181.4	IL 176 (Telegraph Street)
	Harvard	126.17	203.05	US 14 (Division Street)
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Concurrency terminus       Electronic toll collection

Notes[]

• In downtown DeKalb, Route 23 (the main north–south street) intersects as 4th Street with Illinois Route 38 (the main east–west street) at a railroad crossing, as two Union Pacific tracks pass through the crossing. Trains routinely bring traffic in DeKalb to a halt.

References[]

External links[]

Route map:

• Illinois Highway Ends: Illinois Route 23