Cava di Riolite colonnare

The Monte Cinto, approximately 281 meters high, consists of sedimentary rocks in the lower part, formed on the bottom of the ancient sea before volcanic phenomena, and from the mid-slope to the summit, from Rhyolite, a volcanic rock of the second cycle. In this spectacular quarry, the phenomenon known as "columnar jointing" is visible, meaning the subdivision of the rock mass into prisms 40–50 meters high, caused by the mechanism of gradual cooling of the lava immediately after its outflow. The hot mass, in contact with the cold environment, cools quickly from the outside in and can, as is evident in this case, break into very regular prisms.

A curiosity is represented by the hooked bent columns in the upper left corner of the quarry wall, a modification of the original position due to the bending of the lava during the cooling phase and its settling into a position of gravitational equilibrium. The quarry, one of the oldest in the area, has been used since the 1800s for the extraction of volcanic stone (rhyolite and trachyte), commonly referred to as "masegna," used in construction, architecture, road and square paving (e.g., St. Mark's Square in Venice), and in the construction of river and canal embankments. The quarry work was very hard and was divided into three processing phases carried out by quarrymen, cutters, and stone masons.