I could not find out whether it was a former robber's cave. In any case, the access is quite small and narrow and does not invite you to explore. The name Hans Hotzenplotz sounds more like fun to me
You should take a look, the small grotto is part of the Tanzacker circular route. It was built in the steep rocky slope by Italian railway construction workers around 1904 …
Very beautiful crypt on the castle hill, when the castle hill was transformed into a Calvary, 14 Stations of the Cross and the crypt and the grotto "Christ in Chains" were built.