I grew up just south of Land between the Lakes and it's really nice, lots to see and do:
http://www.lbl.org/
If you're into backcountry camping, you're psyched. From the website:
"Unlimited Potential! Have you ever slept under the watchful eye of the Milky Way? At Land Between The Lakes, our lullaby is the gentle lapping of waves on the lakeshore; our alarm clock, the chirping of birds. LBL encompasses 170,000 acres of almost entirely undeveloped land, surrounded on three sides by water a camper's paradise!
LBL has more than 300 miles of shoreline. Many quiet beaches and coves are perfect overnight spots. Hikers and mountain bikers on an extended exploration of our trail system can spend the night trailside, too. So pack your tent and head into the back country for a night under the stars.
Back Country camping is permitted year-round anywhere in LBL except for cemeteries, picnic areas, fee campgrounds, the Environmental Education Area and within 200 yards of paved roads. A Backcountry Camper Use Permit is required. "