Any time it's not really hot is great there. We always tell folks, hike/bike in the
morning, take a cave tour in the afternoon and enjoy the shaded camp ground
the rest of the time. It typically cools off after sunset unless it's really muggy.
As I said, it's a good CG and we usually spend a couple days there every
year. They accept reservations on the front loop, closer to the park road.
Some traffic during the day but pretty quiet at night. There are 2 rear
loops, C & D that are "walk up" which means first come first served.
It can get a little crowded on prime weekends but we always go without
reservations. We also go in week now that we are retired. Last week the
CG was less than 1/4 full.
Bring your bikes they have streets you can ride as well as a great thru the
woods packed gravel trail that goes on for miles.
If you want a popular cave tour you are advised to reserve it at least a
day or 2 ahead or more.
There are also some good hikes near the visitor center and out of the CG
as well as miles and miles of back country trails if that's your thing.