hiking, biking, exploring and visiting local neat things, sitting by the fire in the evening, taking in the evening programs at campgrounds, activities with the grandkids and/or kids when they come, dinners in the dutch oven or over the campfire, sightseeing.
And when the weather turns bad, cribbage, catching up on our list of books and magazines, dominos, DW likes to play "hand and foot" with those who knows how. (Or she will teach you!), pegs and jokers.
Note that TV or DVD's isn't on our list. It's really rare for us to turn on the TV even for a movie when we are camping. Our trailer was several years old before our grandkids realized it even had a TV (It drops into the credenza)