We stayed one night and arrived late without reservations. We found a spot in the C Loop where there were many other tent campers and several unoccupied sites. The wildlife we saw and heard was enjoyable. The boys also did their running on trails in the area. Close to the Visitor's Center for cave tours and a really nice setting for camping.
The location of the sprawling campground is beautiful on the popular Dale Hollow Lake. The kids enjoyed the beach. However, the tent sites were limited to the inner circle areas, as opposed to the right on the water with great views for the concrete-heavy RV sites. However, the worst part was the size and placement of the tent sites. they are tiny and I have no idea how anyone would find the space, much less a level spot, for a normal family tent. We didn't actually stay within our site with 2 small 2-person backpacking tents. We considered using an RV site but didn't see one with level grassy areas.
Edited: We were camped illegally on the grass. Tents are supposed to be on the uneven gravel pads. So 3 tent sites and their parking have a maybe 40 x 50 gravel/asphalt area.
There has to be better places to tent camp in this beautiful area