The Bettlachstock rises out of the first Jura chain like a giant mossy tree trunk. The two half cycles of the Gigler and Brüggli brooks, which lie close to each other, meet in the north of the stock due to retrograde erosion and thus detach it from the mountain range like an island. The impression of an island mountain is further reinforced by the steeply sloping Wandfluh in the north.
Due to the high structural diversity and quality as well as the low level of human disturbance, the diversity of animal and plant species in the area is very high. Beech forests with a high proportion of old trees, standing as well as lying deadwood provide an ideal habitat.
The World Heritage Site includes the few remaining virgin beech forests and centuries-old areas of beech forest unaltered by man in Europe.
