I-474 highlighted in red
|Auxiliary route of I-74|
|Maintained by IDOT|
|Length||14.88 mi (23.95 km)|
|West end||I-74 / IL 6 in Peoria|
| US 24 in Bartonville|
US 24 in Creve Coeur
|East end||I-74 in East Peoria|
Interstate 474 (I-474) is an Interstate Highway loop route that provides a southwestern bypass around the north central Illinois city of Peoria. I-474's parent interstate is I-74. As the first digit of the interstate's number is even, it follows the established convention of providing a loop around a city. Interstate 474 is 14.88 miles (23.95 km) long. I-474 is the highest numbered route in the state of Illinois. It is also, excluding the proposed I-274 in North Carolina, the only auxiliary route of I-74.
Interstate 474 is a modern, Interstate-standard four-lane freeway for its entire length. Prior to 2006, thru truck traffic on I-74 was instructed to use I-474. This is because prior to its 2004-2007 reconstruction, Interstate 74 was significantly below Interstate standard, having numerous 15 mph (24 km/h) onramps and offramps, extremely short merging space for onramps (some less than 500 feet (152 m) in length), 
The western terminus of I-474 is at I-74 exit 87A. The eastern terminus of I-474 is at I-74 exit 99. North of the western terminus, the road continues as Illinois Route 6 with a new series of exit numbers.
I-474 was constructed through the mid-1970s. The now-named Shade-Lohmann Bridge was erected in 1973. During that year, $30.1 million was allocated for acquisition of right-of-way, grading work and overpass/bridge construction across the whole length of the highway.
|Peoria||||0.00||0.00||IL 6 north – Chillicothe||Continuation north beyond I-74|
|0||I-74 – Peoria, Moline, Rock Island||Western terminus; signed as exits 0A (east) and 0B (west); I-74 exit 87A|
|Bellevue||3.78||6.08||3A||To IL 116 – Farmington|
|Bartonville–Peoria line||7.09||11.41||6||US 24 west (Adams Street) – Bartonville||West end of US 24 overlap; signed as exits 6A (US 24 west) & 6B (Adams Street) westbound|
|Tazewell||Creve Coeur||9.57||15.40||9||US 24 east / IL 29 – East Peoria, Pekin||East end of US 24 overlap|
|East Peoria||14.88||23.95||15||I-74 to I-155 south – Peoria, Indianapolis, Lincoln||Eastbound exit and westbound entrance; eastern terminus and signed as exit 15 (west); I-74 exit 99|
|1.000 mi = 1.609 km; 1.000 km = 0.621 mi|
- Kurumi. 3-digit Interstates from I-74. Last updated November 24, 2005. Retrieved March 27, 2006.
- Illinois Technology Transfer Center (2006). "T2 GIS Data". Retrieved 2007-11-08.
- "USGS Map of Peoria, Illinois" (Map). ngmdb.usgs.gov. Retrieved September 22, 2020.
- Illinois Department of Transportation. Image of eastern end of project maps from Peoria to Macomb IDOT site. Retrieved March 27, 2006.
- R.L. Polk and Company (1973), Polk's Peoria City Directory, R.L. Polk and Co. Publishers