The State of Illinois is a state of the United States of America, the 21st to be admitted to the Union. Illinois is the most populous state in the Midwest and the fifth most populous in the nation, and has a large and cosmopolitan population. Its balance of vast suburbs and the great metropolis of Chicago in the northeast, rural areas, small industrial cities, and renowned agricultural productivity in central and western Illinois, and the coal mines of the south give it a highly diverse economic base. Its central location, connecting the Great Lakes to the Mississippi River via the Illinois River, made it a transportation hub for 150 years. With a mixture of factory and farm, urban and rural, Illinois is a microcosm of the United States; an Associated Press analysis of 21 demographic factors determined Illinois was the 'most average state.' Illinois apartments for rent comparison page shows most up to date rent information on Illinois apartments and houses. Rent information is obtained from multiple rental sources but we cannot guarantee their accuracy.