Illinois Route 100 (IL-100) is a
state highway
A state highway, state road, or state route (and the equivalent provincial highway, provincial road, or provincial route) is usually a road that is either ''numbered'' or ''maintained'' by a sub-national state or province. A road numbered by a ...
in the southwest
Illinois
Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. Its largest metropolitan areas include the Chicago metropolitan area, and the Metro East section, of Greater St. Louis. Other smaller metropolita ...
. It generally parallels the
Illinois River
The Illinois River ( mia, Inoka Siipiiwi) is a principal tributary of the Mississippi River and is approximately long. Located in the U.S. state of Illinois, it has a drainage basin of . The Illinois River begins at the confluence of the D ...
. Starting in downtown
Alton
Alton may refer to:
People
*Alton (given name)
*Alton (surname)
Places Australia
*Alton National Park, Queensland
* Alton, Queensland, a town in the Shire of Balonne
Canada
* Alton, Ontario
*Alton, Nova Scotia
New Zealand
* Alton, New Zealand, ...
, it trends northward to
Buckheart Township near
Canton. It makes up much of the
Illinois River Road, a U.S.
National Scenic Byway
A National Scenic Byway is a road recognized by the United States Department of Transportation for one or more of six "intrinsic qualities": archeological, cultural, historic, natural, recreational, and scenic. The program was established by Co ...
.
Route description
The southern end in Alton is at US 67 where Broadway, Landmarks, and Piasa Streets come together. It follows the east bank of the Mississippi River and Illinois River through Grafton until Hardin, where it crosses the Joe Page Bridge across the Illinois River. A portion of the Great River Road was on an old railroad alignment, which you can see parts of just north of Alton. During periods of high water, this highway is susceptible to flooding.
North of Hardin, the highway follows the west bank of the Illinois River until the bridge near Florence. From that point on, IL 100 follows mostly farmland on much higher ground until Beardstown, where it will cross the river a third and final time. It will again follow the west bank of the Illinois River until US 136. After meeting with US 24 in Duncan Mills, IL 100 and US 24 is cosigned until Lewistown. North of Lewistown, IL 100 heads in a north-east alignment until its northern terminus with IL 78 near Dunfermline.
Illinois River Road
Illinois Route 100 overlaps the Illinois River Road from Grafton to
Detroit
Detroit ( , ; , ) is the largest city in the U.S. state of Michigan. It is also the largest U.S. city on the United States–Canada border, and the seat of government of Wayne County. The City of Detroit had a population of 639,111 at th ...
.
History
IL 100 originally went from Godfrey from the intersection at Godfrey Road and Homer M. Adams Parkway (IL 111/US 67) to Grafton on the current IL 3. In 1987, IL 3, 143, and 100 alignments were changed to their current routes in the
River Bend (Illinois)
The River Bend is a small region in western central Illinois and Southern Illinois that comprises parts of Madison County and Jersey County. The name comes from a section of the Mississippi River that flows roughly west to east instead of the u ...
area when the Homer M. Adams Parkway Extension was opened. On June 28, 2012, the Florence Bridge over the Illinois River was closed for at least 9 months by IDOT due to difficulties with the lifting mechanism that allows barge traffic to pass under the bridge. Inspections suggested that continued use of the lift span could harm the structural integrity of the bridge. As barges need to pass under the bridge, the lifting span was raised up and the bridge was closed. Motorists wishing to cross the river must use the signed detour utilizing
Illinois Route 106,
US Route 54
U.S. Route 54 (US 54) is an east–west United States Highway that runs northeast–southwest for from El Paso, Texas, to Griggsville, Illinois. The Union Pacific Railroad's Tucumcari Line (former Southern Pacific and Rock Island Lines "Golden ...
, and
Interstate 72
Interstate 72 (I-72) is an Interstate Highway in the midwestern United States. Its western terminus is in Hannibal, Missouri, at an intersection with U.S. Route 61 (US 61); its eastern terminus is at Country Fair Drive in Champ ...
/
US Route 36
U.S. Route 36 (US 36) is an east–west United States highway that travels approximately from Rocky Mountain National Park, Colorado to Uhrichsville, Ohio. The highway's western terminus is at Deer Ridge Junction, an intersection in ...
. The bridge was repaired and reopened to traffic on April 22, 2013, only to be closed again for seven days of repairs after a barge collision on June 20, 2019.
Major intersections
References
External links
{{ccat
Illinois Highway Ends: Illinois Route 100National Scenic Byways
100
100
Transportation in Madison County, Illinois
Transportation in Fulton County, Illinois
Alton, Illinois
Transportation in Jersey County, Illinois
Transportation in Greene County, Illinois
Transportation in Calhoun County, Illinois
Transportation in Pike County, Illinois
Transportation in Scott County, Illinois
Transportation in Morgan County, Illinois
Transportation in Cass County, Illinois
Transportation in Schuyler County, Illinois