Shabbona Lake State Park

Have been coming here for years when the kids were small, before full-timing. This park is a top camping draw for families from The City and fills almost every Summer weekend, during the week not even a tenth filled.
This park features a big fishing and paddle sports lake, no motors over 10hp. Buy a license! DNR Police are active here.
The day-use and camping sections are separate and distinct. There is a restaurant at the day-use side and a great camp store with fishing and camping supplies as well as food and ice cream treats on the camping side.
There are boat rentals at each location.
There are 150 camp sites, FCFS and ReserveAmerica. They are all back-in, electric only, level is debatable. The park works hard to keep the woods at bay and is constantly pushing it back, but the sites are still very woodsy, many are in twilight all day. The State Park has a booster club and many supporters. See this web site, not Illinois DNR, for lots of info about the lake and park, as well as pictures of the camping sites and lots of fish pics:

http://shabbonalake.com/camp-site-photos/

This is a camping park mostly tent camping, pop-ups, and travel trailers. Motorized RV are probably truck campers and small rv's. Check the photos in the above noted web site. Large Class A's and 5th wheels would have a chore getting in. There is a fire ring and picnic table at every site and there is plenty of grass around before giving way to the woods.
There are good hiking trails, including a formidable one around the lake.
Families and children play all day and never stop exploring the woods. This is not a quiet place...it is not supposed to be.
Besides the usual outhouses there is a single shower and bathroom building which, though cleaned daily, is severely taxed when the park is full. It is rather Spartan, at best.
Four host couples, scattered about the park keep things running smoothly without spoiling the fun.