Off the beaten track, the undulating plateau of Swiss Franconia (southwest of Bayreuth), is gashed by deep valleys. It forms the northern extremity of the Jura and its porous limestone shelf has resulted in many caves. The Devil's caves (Teufelshöle) are among the largest, adorned with impressive stalactites and stalagmites, in particular the "Cathedral of Barbarossa". The cave's exit, through a labyrinth of massive, chaotically heaped rocks, is picturesque.