Porphyry Fan in Tharandt Forest

In the 19th century, a roughly 40 meter wide and 22 meter high "quartz-poor porphyry" was visible through a quarry. About 290 million years ago, porphyry magma escaped explosively from the “Grunder column”. The material buried valleys and valleys and gradually cooled down. When cooling down, the volume decreased - first on the surface, then ever deeper. As a result, cracks formed until the columnar rock segregation ultimately emerged.

Very interesting geological rock formations. It is about 10 minutes from the Mohorn-Grund hiking car park to the porphyry fan.

With its special and varied geological features (e.g. with formations and rocks from various geological eras), the Tharandt Forest forms the core of the Geopark Sachsens Mitte. There is now a new, beautifully designed shelter near the fan, ideal for resting & learning about geological events.