Only been to CC 4-5 times and always stay with friends in Clinton/Norris/Oak Ridge.
Haven't ever stayed there, but the campgrounds all new and pretty nice from what I recall. Several lower end hotels/motels nearby in Oliver Springs or just down the road in Oak Ridge.
Once there, park in HUGE graveled lots and drive your rig anywhere on that property without fear. However, anything you leave in the lot better be locked up!
Without someone to guide you (I don't recall the map or trail marking being that good), you can ride for days and never see the the same trails. OTOH, you can also QUICKLY find the trails you shouldn't be on or are way too tame for your rigs.