Hinterrugg  The Hinterrugg (or Hinderrugg) is the highest peak of the Churfirsten group, located in the Appenzell Alps. It overlooks the town of Walenstadt and the lake in the canton of St. Gallen. The summit is easily accessible via the Chäserrugg cable car station (2,262 metres), above Unterwasser in Toggenburg. The Hinterrugg is a well-known location for BASE jumping.