Interstate 70 in Illinois
|Maintained by IDOT|
|Length:||160 mi (257 km)|
|West end:||US 40 / I-55 / I-64 / I-70 in East St. Louis|
|US 40 near Marshall|
|East end:||US 40 / I-70 near Marshall|
|Counties:||St. Clair, Madison, Bond, Fayette, Effingham, Cumberland, Clark|
Interstate 70 (I-70) is a part of the Interstate Highway System that runs from Cove Fort, Utah to Baltimore, Maryland. In the U.S. state of Illinois, the Interstate highway runs 160 miles (260 km) from the Missouri state line at the Mississippi River in East St. Louis east to the Indiana state line near Marshall. I-70, which runs in a generally east-northeast direction across the state parallel to and sometimes concurrent with U.S. Route 40 (US 40), connects St. Louis and the Metro-East region of Illinois with the Indiana cities of Terre Haute and Indianapolis, as well as many small towns along the northern edge of Southern Illinois and the southern tier of the Central Illinois region. Within Metro-East, I-70 has junctions with I-64 in East St. Louis and I-55 near Troy; these three Interstates cross the Mississippi River into St. Louis together. I-70 also intersects the two Interstates that form St. Louis's beltway: I-255 near Collinsville and I-270 at the I-55 junction near Troy. East of the Metro-East region, I-70 meets US 51 in Vandalia and both I-57 and US 45 in Effingham. Like all Interstate highways, I-70 is a part of the National Highway System for its entire length in Illinois.
Route description 
I-70 enters Illinois from St. Louis by crossing the Mississippi River on the eight-lane Poplar Street Bridge into the city of East St. Louis in St. Clair County. I-70 runs concurrently with I-55, I-64, and US 40 entering the state. At the east end of the bridge, the Interstate splits into express and local lanes, both with two lanes each direction, as it passes through a pair of directional interchanges. The first interchange is for IL 3, which heads south toward Cahokia, and the second is for Tudor Avenue and Piggott Avenue, which form a one-way pair in a residential area of East St. Louis. The east end of the interchange complex has an eastbound exit to Fourth Street and a westbound entrance from Main Street. IL 3 joins the highway to form a five-way concurrency, which reduces from eight to six lanes. The Interstate curves around downtown East St. Louis and has two partial interchanges, both with westbound exit and eastbound entrance, for the Martin Luther King Bridge and Eads Bridge toward Downtown St. Louis; both roadways temporarily expand to five lanes. I-64 and IL 3 (St. Clair Avenue) leave the concurrency at the next interchange, taking two lanes from each direction. I-70 and I-55 have a westbound exit to and eastbound entrance from Exchange Street before the Interstate leaves the city of East St. Louis by crossing over the main east–west railroad line.
I-70 and I-55 have an interchange with IL 203 before entering Madison County. The Interstate has a diamond interchange with IL 111 just north of Fairmont City and a partial interchange with Black Lane before the highway's interchange with I-255 west of Collinsville. I-70 and I-55 curve northeast around Collinsville and leave the floodplain of the Mississippi River at the interchange with IL 157 (Bluff Road), where the highway reduces to four lanes. The Interstate passes between Collinsville and Maryville, which are both served by the next interchange with IL 159 (Vandalia Street/Maryville Road). US 40 leaves the freeway at a trumpet interchange southwest of Troy. I-70 and I-55 curve to the north and meet IL 162 (Edwardsville Road) before I-70 and I-55 diverge at the highways' interchange with I-270. The interchange, Exit 20, is a full cloverleaf except for a flyover ramp for westbound I-70 to join southbound I-55. Westbound I-70's interchange number is Exit 15, marking the continuation of I-270's number sequence that I-70 will carry east to Indiana.
I-70 meets IL 4 and IL 143 to the south and east of Marine before crossing Highland Silver Lake. US 40 joins I-70 again near Pierron, Illinois and run concurrently into Bond County, where the highways separate at Pocahontas, where I-70 crosses Shoal Creek. US 40 continues to closely parallel I-70 until the next interchange, which is a connector to US 40 southwest of Greenville. The two highways pass to the south of Greenville, which is also served via an interchange with IL 127. East of Mulberry Grove, I-70 and US 40 cross to the north side of the east–west rail line and again closely parallel each other into Fayette County. I-70 passes along the northern edge of Vandalia, with access to the county seat of Fayette County provided by an interchange with US 40 on the west side and US 51 (Kennedy Boulevard) to the north. Just east of US 51, I-70 crosses the Kaskaskia River. I-70 crosses to the south side of both the rail line and US 40 (Cumberland Road) between Bluff City and Brownstown. The Interstate passes to the south of St. Elmo before entering Effingham County to the west of an interchange with IL 128 at Altamont.
Immediately after crossing the Little Wabash River, I-70 joins I-57 in a concurrency to pass around the west and north sides of Effingham. The two Interstates use I-57's exit sequence during the overlap. I-70 and I-57 intersect Fayette Avenue, IL 32 and IL 33 (Keller Drive), and US 45 (Third Street) before diverging near Teutopolis. Just east of Montrose, I-70 enters Cumberland County, where the Interstate has one interchange with IL 130 (Haughton Highway) at Greenup, where the highway crosses the Embarras River. The Interstate continues into Clark County for an interchange with IL 49 north of Casey. I-70 crosses the North Fork Embarras River north of Martinsville, then has a junction with IL 1 north of the county seat of Marshall. Northeast of Marshall, US 40 joins I-70 in a concurrency. The Interstate and U.S. highway cross the Indiana state line west of Terre Haute while closely paralleling the original alignment of US 40, Illiana Drive.
Exit list 
I-70 uses the I-55 exit number sequence between the Missouri state line and the I-55/I-70/I-270 interchange (exits 1–20). East of the I-55/I-70/I-270 interchange, I-70 uses the I-270 exit numbering, beginning with exit 15 at I-55/I-70/I-270. I-70 uses I-57's exit number sequence during their overlap around Effingham.
||East St. Louis||—||I-70 west / I-55 south / I-64 west / US 40 west – St. Louis, Kansas City||Western terminus of I-70 in Illinois; Missouri state line on the Poplar Street Bridge over the Mississippi River|
|1||IL 3 south / Great River Road – Cahokia||West end of IL 3 overlap|
|2A||Martin Luther King Bridge – Downtown St. Louis||Westbound exit and eastbound entrance|
|2B||Great River Road – Eads Bridge||Westbound exit and eastbound entrance|
|2C||I-64 east / IL 3 north (St. Clair Avenue) – Louisville||Signed as exit 2 eastbound; East end of IL 3 overlap; East end of I-64 overlap|
|3||Exchange Avenue||Westbound exit and eastbound entrance|
|Canteen Township||4||IL 203 – Granite City, Fairmont City||Split into exits 4A (south) and 4B (north) westbound|
||Nameoki Township||6||IL 111 / Great River Road – Wood River, Washington Park|
|9||Black Lane south||Eastbound exit and westbound entrance|
|Collinsville Township||10||I-255 – Memphis, Interstate 270|
|11||IL 157 (Bluff Road) – Collinsville, Edwardsville|
|Maryville||15||IL 159 (Vandalia Street/Maryville Road) – Collinsville, Maryville||Split into exits 15A (south) and 15B (north)|
|Jarvis Township||17||US 40 – St. Jacob, Highland||East end of US 40 overlap|
|Troy||18||IL 162 (Edwardsville Road) – Troy|
|Pin Oak Township||20/15||I-55 north / I-270 west – Springfield, Chicago, Kansas City||East end of I-55 overlap; Split into exits 20A (I-70) and 2B (I-270) eastbound, with no exit number for I-55; Exit 15B westbound is for I-55, with no exit number for I-270|
|Marine Township||21||IL 4 – Staunton, Lebanon|
|24||IL 143 – Marine, Highland|
|Saline Township||30||US 40 west / IL 143 (Steiner Road) – Pierron, Highland||West end of US 40 overlap|
||Old Ripley Township||36||US 40 east (Pokey Road) – Pocahontas||East end of US 40 overlap|
|Central Township||41||To US 40 / Millersburg Road – Greenville|
|45||IL 127 – Greenville, Carlyle|
|Pleasant Mound Township||52||Mulberry Grove Road – Mulberry Grove, Keyesport|
||Vandalia Township||61||US 40 – Vandalia|
|Vandalia||63||US 51 (Kennedy Boulevard) – Vandalia, Pana|
|Otego Township||68||US 40 (Cumberland Road) – Brownstown, Bluff City|
|St. Elmo||76||Interstate Drive – St. Elmo|
||Altamont||82||IL 128 north (Main Street) – Altamont|
|Summit Township||92||I-57 south – Memphis||West end of I-57 overlap; Westbound I-70 exits I-57 via exit 157|
|Effingham||159||Fayette Avenue – Effingham|
|160||IL 32 / IL 33 (Keller Drive)|
|162||US 45 (Third Street) – Sigel|
|Teutopolis Township||98||I-57 north – Chicago||East end of I-57 overlap; Eastbound I-70 exits I-57 via exit 163|
|Montrose||105||Spring Creek Road – Montrose|
||Greenup||119||IL 130 (Haughton Highway) – Greenup, Charleston|
||Casey Township||129||IL 49 – Casey|
|Martinsville||136||Cleone Road – Martinsville|
|Marshall Township||147||IL 1 – Marshall, Paris|
|Wabash Township||154||US 40 west||West end of US 40 overlap|
|—||I-70 / US 40 east – Terre Haute, Indianapolis||Eastern terminus of I-70 in Illinois; Indiana state line|
- Google Inc. Google Maps – Interstate 70 in Illinois (Map). Cartography by Google, Inc. http://maps.google.com/maps?f=d&source=s_d&saddr=I-70+E&daddr=I-70+E&hl=en&geocode=FSRDTQId8-uf-g%3BFZbAWQIdpWDI-g&mra=ls&sll=39.435398,-87.534556&sspn=0.007607,0.01929&ie=UTF8&t=h&z=8. Retrieved 2011-01-24.
- Federal Highway Administration (July 2003) (PDF). National Highway System: Illinois (Map). http://www.fhwa.dot.gov/planning/nhs/maps/il/il_Illinois.pdf. Retrieved 2011-01-25.