drinking beer
Even though this does not seem to be an activity on its own it can easily become one in the franconian swiss. As said the density of breweries is the highest here all over the world and literally every village has its own pub serving home brewed yeast juice at very reasonable prices and hefty franconian local cuisine.
rock climbing
The franconian swiss is, though not the cradle, the mekka of german and european rock climbers. Every climber has to come here once in his lifetime to have at least a look at the famous action-direct climb. The limestone in this area is plentiful and the local scenery and breweries make it a nice weekend retreat. For german standards the safety amount and quality of bolts is really high here, though it does not reach the french standards. See (http://www.frankenjura.com/) for online topos and access descriptions.