In the summer, whoever visits the cave is amazed by the intensity of the wind coming from deep inside the mountain when a re-enforced steel door is opened. This discomfort only lasts a short time because, as soon as the guides closes the door, the wind and the cold suddenly stop.

The temperature in the most internal parts, all year round is +10,7° C., a figure which corresponds to the average annual temperature. There are two openings: the lower one is the current entrance for tourists and is at 642 metres above sea level, the higher one is located at a height of 1400 metres, on the opposite side of the mountain.
There is consequently an air current about 800 metres high, free at both ends, that during summer is colder and heavier than the air outside, so it precipitates downwards creating a strong outgoing wind at the lower entrance, meanwhile relatively hot air is drawn in through the higher entrance which, running through the cave, cools down and maintains a continuous circulation.

The air circulation in winter.
The air inside is hotter than outside and flows upwards creating an incoming wind at the lower entrance that heats up inside the cave and continues circulating up.

The air circulation in summer.
The air inside is colder than outside and so heavier. It moves downwards, hot air is drawn in through the higher entrance and cools down inside maintaining the downward circulation.

In the winter the situation is reversed: the air inside, hotter and therefore lighter than that outside,  quickly flows up, creating an incoming wind at the lower entrance that heats up when it enters, constantly maintaining the circulation towards the top.
The speed of the wind is directionally proportional to the difference between the temperature inside and outside; when both temperatures are equal all air currents stop.