Illinois is a state located in the Midwestern region of the United States. Known for its diverse landscapes, it features urban areas like Chicago, the third-largest city in the U.S., as well as vast farmland and beautiful state parks. The state is rich in history and culture, being home to significant landmarks such as Abraham Lincoln's home in Springfield and the Willis Tower. Illinois plays a vital role in transportation and commerce, making it a key player in the nation's economy.