Western Illinois is a region of Illinois generally bounded by the Mississippi River to the west, I-80 to the north and I-39/I-55 to the east. It has two major anchors: Peoria and the Illinois side of the Quad Cities. Being culturally similar to Central Illinois, they are sometimes presented together as the same region.
- Forgottonia: A tongue-in-cheek, self-given name for much of the area between the Illinois and Mississippi Rivers that had a brief independence movement in the 1970s.
- The Illinois Quad Cities—4-headed metro region in western Illinois and Eastern Iowa containing Rock Island and Moline. Davenport and Bettendorf are on the Iowa side of the Mississippi.
- Greater Peoria: The region immediately surrounding Peoria.
- Arenzville - home of the Arenzville Burgoo
- Nauvoo - original home of LDS founder Joseph Smith
- Peoria - the largest city in Western Illinois, Peoria is home to Bradley University, an interesting riverfront with minor-league baseball and is also home to headquarters of Caterpillar and other large companies.
- East Peoria
- Moline (home of Western Illinois University - Quad Cities Campus) and Rock Island - two of the Quad Cities
- Jacksonville- home of Illinois College, the first college in the state
- Washington - unique town with big city conveniences and small town charm.
- Galesburg - home of Knox College
- Macomb - home to Western Illinois University
The best way to travel throughout the region is by car. I-74 is the primary thoroughfare and connects anchor cities Peoria and Rock Island. It also provides service to the Illinois Twin Cities (Bloomington and Normal) and the Urbana and Champaign area. US 24 serves as a secondary thoroughfare and connects Peoria to Quincy another anchor city located on the Mississippi. Interstate 72 also provides some service to the southern portions of the region.