Illinois Route 170 is a north–south state road in north-central Illinois

Illinois

Illinois is the fifth-most populous state of the United States of America, and is often noted for being a microcosm of the entire country. With Chicago in the northeast, small industrial cities and great agricultural productivity in central and northern Illinois, and natural resources like coal,...

. It runs from Illinois Route 23

Illinois Route 23

Illinois Route 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 .-Route description:...

 well north of Pontiac

Pontiac, Illinois

Pontiac is a city in Livingston County, Illinois, United States. The population was 11,931 at the 2010 census. It is the county seat of Livingston County...

 to U.S. Route 6

U.S. Route 6

U.S. Route 6 , also called the Grand Army of the Republic Highway, a name that honors an American Civil War veterans association, is a main route of the U.S. Highway system, running east-northeast from Bishop, California to Provincetown, Massachusetts. Until 1964, it continued south from Bishop to...

 in Seneca

Seneca, Illinois

Seneca is a village in LaSalle and Grundy counties in the U.S. state of Illinois. The population was 2,371 at the 2010 census.The LaSalle County portion of Seneca is part of the Ottawa–Streator Micropolitan Statistical Area, while the small portion that lies in Grundy County is part of the...

. This is a distance of 25 miles (40.23 km).

Route description

Illinois 170 is a rural, two-lane surface road for its entire length. The road crosses Illinois River

Illinois River

The Illinois River is a principal tributary of the Mississippi River, approximately long, in the State of Illinois. The river drains a large section of central Illinois, with a drainage basin of . This river was important among Native Americans and early French traders as the principal water route...

 via a four-span truss bridge

Truss bridge

A truss bridge is a bridge composed of connected elements which may be stressed from tension, compression, or sometimes both in response to dynamic loads. Truss bridges are one of the oldest types of modern bridges...

. As of May 5, 2006, the Illinois Department of Transportation

Illinois Department of Transportation

The Illinois Department of Transportation is a state agency in charge of state-maintained public roadways of the U.S. state of Illinois. In addition, IDOT provides funding for rail, public transit and airport projects and administers fuel tax and federal funding to local juridictions in the...

 is looking to replace the 74 year old bridge. The old bridge was imploded on November 18, 2010.

History

SBI Route 160 originally ran from Red Bud

Red Bud, Illinois

Red Bud is a city in Randolph County, Illinois. The population was 3,422 at the 2000 census.It is the home of the of Southwestern Illinois College.-Geography:Red Bud is located at ....

 to Sparta

Sparta, Illinois

Sparta is a city in Randolph County, Illinois, United States. The population was 4,486 at the 2000 census.The city was the principal filming location for the 1967 film In the Heat of the Night.-Geography:Sparta is located at ....

; this became Illinois Route 154

Illinois Route 154

Illinois Route 154 is an east–west state road in southern Illinois. It runs from Illinois Route 3 in Red Bud to Illinois Route 37 in Whittington. This is a distance of .- Route description :...

 in 1937. In 1946, it replaced Illinois Route 186 from Seneca south to Illinois Route 17

Illinois Route 17

Illinois Route 17 is a rural, arterial east–west state road that runs east from a former ferry crossing in New Boston along the banks of the Mississippi River to State Road 2 west of Lowell, Indiana. It is long.- Route description :...

 near Budd. In 1995 Illinois 170 was extended further south to Illinois 23.