Illinois GuideIllinois is a state in the Midwest of the United States of America. Central Illinois Chicagoland Northern Illinois Saint Louis Metro East Southern Illinois Western Illinois Illinois is a mostly flat plains state, with the majority being farmland except for the river valleys and the south, which are hilly and forested. HotelsFind hotels in Chicago, Rosemont, Caseyville and more. ChicagoChicago is the home of the blues and the truth of jazz, the heart of comedy and the idea of the skyscrapers. Champaign-UrbanaChampaign-Urbana is a metropolitan area in central Illinois, composed of the towns of Champaign, Urbana, and Savoy. ChicagolandChicagoland consists of the Chicago metropolitan area in northeastern Illinois, including Chicago and its surrounding suburbs. Central IllinoisCentral Illinois is a region of Illinois extending south from Chicagoland along the border with Indiana. Saint Louis Metro EastThe St. Louis metropolitan area is mostly in Missouri to the west and north of the city, but it does spill over into Illinois to some degree, especially to the north-east and along a line toward Belleville Illinois to the east. Northern IllinoisNorthern Illinois is a region of Illinois. Northern Illinois is generally considered to be the area of Illinois north of I-80 and outside of Chicagoland. Western IllinoisWestern 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. Southern IllinoisSouthern Illinois is a region in the state of Illinois in the United States of America.