Geoturism and geomorphological hazard: the Rocca d'Olgisio case study (Northern Apennine, Italy)

The Val Tidone is a sector of the Piacenza Apennine (Northern Apennines, Italy), and is characterized by a morphostructure that is very important from scientific and didactic points of view. It is a synclinal mountain, the remains of a larger folded structure showing inverted relief, where a “canoe-shaped” valley appears level with a “synclinal perché,” as defined by French authors. Besides being an area of particular interest for its geologic and geomorphologic characteristics, it is also significant from a historical point of view. In fact, the imposing medieval fortress of Rocca d’Olgisio sits on the rock near the “canoe’s prow.” Moreover, it is hypothesized that the caves that are above the castle along the steep slopes characterising each side have been frequented by humans at various times. The area also has interesting biodiversity because of the occurrence of rare and unusual species of plants, such as dwarf Indian figs, orchids and cork trees, which have appeared thanks to the particular microclimate and peculiar soil conditions. This site is currently crossed by a pathway running mainly along the “canoe’s nose.” The use of this pathway should necessarily take into account the natural hazard due to the particular litho-structural, geomorphologic and climatic conditions (e.g., landslide hazard, weathering). For this reason, it is necessary for users to be trained and aware of hazardous areas. Hence, it is important to provide protective structures and bars. Finally, problems related to frequenting the area should not be omitted, in order to reduce, as much as possible, negative consequences for the natural heritage.