The Indian Caves
Before this area was settled by pioneers, the Patowatami indians and Native Americans lived there for many centuries. They lived along the bank of what we know as the Kankakee River, they called it the Theatiki river. But with the series of mispronouncing and misspelling the word became "Kankakee."
I believe it is a wonder because it covers 30 acres of land. Also, the caves are really small, the deepest cave is about 20 feet deep. If you were going to enter it you would have to enter a very narrow crevice in the rock. In 1996 governor Jim Edgar even opened it to public (but not to go in it) so everyone can see this amazing wonder. This wonder is so amazing that Jim Edgar attempted to protect it from vandalism and other harming things to this work of art of the Patowatami indians
This wonder is a great site to see. You should check it out over Prairie farms Bourbonnais, IL.