Bobert, there are swimming pools, fitness rooms, spas (so you can get your nails done), libraries, even chaplains. On a history cruise you'll probably have lectures (not the boring kind) by people who actually know something about the area. If nothing else you can sleep all the time. You gotta have swimming suit to use the pool -- none of that hillbilly swimmin'. Hell, I've even heard of cruises where they shot skeet off the back of the boat.
Just don't get too far from your life jacket...and be sure to get one for your geetar iffen you bring it.