Following the red path of the Monterano Nature Reserve, you descend along a steep slope that after many meters and just as many steps reaches a crack in the rock that is really deep, just a meter wide in its widest sections and long as far as the eye can see. This is the Etruscan cut, also called "il Cavone". A path dug into the rock by the Etruscans that allowed you to easily reach the nearby Bicione ditch, one of the two streams that surround the Ancient Monterano. Unfortunately, during the busiest periods of the year, it is forbidden to travel it, due to some landslides and collapses that have occurred recently. Once you reach the plateau below, your sight and smell are amazed. Coming out of the last curves of the path, in fact, you find yourself in front of an unexpected spectacle, the Zolfatara: an enormous spring of sulfurous water that immerses the visitor in a volcanic environment without any waning. This valley was exploited for mining until the last century: initially for the extraction of sulfur, present in very large quantities, then for other minerals, such as pyrite and iron. However, the tunnels that run through it have not been in use for at least 50 years.