The Birnbachloch with its 20 meter wide entrance is located east of the Birnbach Glacier at 1,291 meters. There are many karst springs like these in the Leogang Steinberge, but …
The Barbara Tunnel is a beautiful highlight in the Leogang region. A trip there is always worthwhile. The mountain guides are passionate, and groups are manageable. Booking online is a good idea.