Illinois provides an interesting slice of the Midwest, a combination of the urban, sophisticated delights of Chicago and the much more laid-back "downstate" (everywhere that is not Chicago), where Lincoln lore and other rural attractions recall the Illinois of the 1800s.
Illinois' dual identity is a blessing for vacationers. They can experience the urban glamour of Chicago's world-class museums, shopping, restaurants and nightlife and then unwind in the tranquil countryside's vintage architecture and historic sites.