...an incomprehensive review.
Illinois Beach State Park is one of the two best campgrounds within 40 miles of Chicago, because (though I'm not certain) there are only two such campgrounds. That said, I enjoyed every moment of my overnight trip. I arrived by bicycle and passed the "Campground Full" sign on my way into the park. The campground office informed me 3 sites were flooded and if I thought any were suitable, I should drop off my gear and return to pay the fee. One of the sites was bone dry so I snatched it up.
After making camp, I got a fire going and soon had a pot of oatmeal going on the hot coals. My site was adjacent to one with a public spigot which made it very convenient to fill my 2 gallon reusable water bag. Of course, It is wildly useful to have water on hand.
I got lost in the flames, may have seen the lord of light, and fell sound asleep. Although it rained overnight, I was able to rekindle a fire the next morning (thanks to extra firewood I scavenged from an empty site nearby) for another large serving of oatmeal.
The bathroom facilities were standard campground quality, but as with other campgrounds it is annoying to have to go to the restroom every time I had to pee. Plenty of trees to go behind, but prying/judging eyes in far greater quantity.