I only got to spend a few hours here but it was beautiful. There were plenty of waterfalls and streams and it seemed very secluded. I would definitely go again
For a state park this may be the best one IL has. I have not been to them all but I could go here day in and day out and it would be eventful. Very pretty views of cliffs and waterfalls, if you are debating on visiting, definitely do it.
Cost 5 dollars to get in, it's basically one overlook at the canyon/river and that's it. It was a cool photo opp but I don't think you need to spend more than an hour here. The campsites were the most primitive of primitive and cost 10. I'm sure the night sky would look good