Petit Jean SP is one our favorite when we take our 7 yr old granddaughter camping with us. Area "A" is all FHU (full hookup) and lots of area for kids to run around and play. Areas B, C & D are more rustic, close together in the woods and have water & electric only. Great hiking trails.
For old buildings there are a couple in the park.
About 40 miles from the campground at the community of Pottsville is the "Potts Inn" built in 1857 and used as a Butterfield Stagecoach stop until the start of the Civil War. Serval other old buildings there also. Google it.
For a future trip check out Craters of Diamonds SP. About 30 miles south of there is Old Washington SP. A whole town that is a State Park. There are tours of the old houses. fantastic gun museum and blacksmith shop. The community goes back to the early 1800's. This was on the road to Texas so a lot of history.
Have a great time.
