Just entered the bay of Porto Conte, coming from Punta Giglio we find the cave of the well; this cave is named for its shape very similar to that of an artesian well. The entrance is at a depth of 14 meters, you enter for a large opening 3 meters high and alrga at least triple; the room widens further after the entrance and the top rises.; Inside the cave there are no forms of life in large quantities, sometimes it happens to find there, in the numerous holes of the ceiling some medium-sized cicada or some lobster, some corvinas shelter in the parts most protected from light. Arrived at the end of the cave, looking up, depending on the lighting conditions you can see the light entering from the upper opening placed at 1 meter deep. At this point you go up the "vertical well" until you get to the exit in order to enjoy a "champagne" effect due to the air exhaled during your stay in the cave, air that has permeated the rock and comes out of the many porosities. The return to the boat is simple, the bay is always well sheltered and the large cave lends itself to the first underwater adventures in the cave.