Illinois Route 177
IL 177 highlighted in red
Route information
Maintained by IDOT
Length	47.59 mi[1] (76.59 km)
Existed	1924[2]–present
Major junctions
West end	IL 13 / IL 158 in Belleville
Major intersections	I-64 in Okawville
East end	US 51 in Irvington
Location
Country	United States
State	Illinois
Counties	St. Clair, Clinton, Washington
Highway system
Illinois State Highway System Interstate US State Tollways Scenic
← IL 176 → IL 178

Illinois Route 177 is an east–west state route in southern Illinois. It runs from Illinois Route 13 in Belleville to U.S. Route 51 in Irvington. This is a distance of 47.59 miles (76.59 km).^[1]

Route description

Illinois 177 overlaps Illinois Route 160 for about 9 miles (14 km)^[3] from south of New Baden to Okawville.

History

SBI Route 177 originally ran from New Minden to Okawville. It was extended east to Irvington in 1937, replacing Route 153.^[4] In 1967, it was extended west to Belleville on an old routing of Illinois Route 15.^[2]

Major Intersections

County	Location	mi[5]	km	Destinations	Notes
St. Clair	Belleville	0.0	0.0	IL 13 / IL 158 west – East St. Louis, Columbia, Pinckneyville	West end of IL 158 concurrency
	​	6.3	10.1	IL 158 east – Scott Air Force Base	East end of IL 158 concurrency
	Mascoutah	10.2	16.4	IL 4 (Jefferson Street)
Clinton	​	16.2	26.1	IL 160 north – Highland	West end of IL 160 concurrency
Washington	Okawville	25.1	40.4	IL 160 south (South Front Street) – Addieville	East end of IL 160 concurrency
		26.6	42.8	I-64 – East St. Louis, Mt. Vernon	I-64 exit 41
	New Minden	35.3	56.8	IL 127 – Carlyle, Nashville
	​	47.59	76.59	US 51	interchange
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Concurrency terminus