Hellloch-Sinkhole in the Hintertal

Discover the gigantic sinkhole on the Geophenomena Trail Kerenzerberg!

A few metres to the west of the hiking trail lies a huge sinkhole from an underground cave system - the Hellloch Sinkhole! With a diameter of around 20 m, it is the largest sinkhole in the Tectonic Arena Sardona. The continuous dissolving of limestone creates intricate underground passages along fractures and fissures. These cavities can collapse near the surface and create so-called sinkholes.

Hiking tip: Geophenomena Trail Kerenzerberg 

In October 2015, the Geophenomena Trail was renewed and new information boards explaining the geological phenomena were installed. The trail leads from the Habergschwänd mountain station via the Talalp and Spanegg lakes to the Fronalp Pass and partly follows the official Sardona World Heritage Trail No. 73, so you can learn how glaciers grind rocks, how moraines are formed, how the local rocks write climate histories, and you can read interesting facts about caves, the Talalp lake and the Hellloch doline.

The path between Habergschwänd and the Talsee is 2 kilometres long. On this short stretch you will find rocks with an age difference of up to 100 million years. All of them were formed as deposits on the floor of a sea. Most of them are limestone. In various places they contain fossilised former sea creatures, e.g. assilines. Sometimes whole "animal graveyards" can be found.

Link to the Kerenzerberg Geophenomena Trail