Backbone SP is one of the best in Iowa
I have visited a lot of Iowa parks and campgrounds. Backbone is one on my favorites. Backbone is the oldest state park in Iowa. You can take your canoe out on the lake or hit some of the hiking trails. There are cabins for rent if you don't want to sleep in a tent.
Click on the following link to download the trail maps: www.iowadnr.gov/portals/idnr/uploads/parks/trailmaps/trails_backbone.pdf
This is a great place to stay but make sure you get your reservations in early if you plan on staying on the weekend. If you want it to be quiet and prefer less crowds but you still want to enjoy the park, I highly suggest taking some time off of work during the week and avoiding the weekend.
This is a special place, the facilities, the showers, the campsites, the trails, and the lake are top quality.