1998-1999: reconnaissances During two investigations carried out in November 1998 and May 1999 two large caves located downhill, both near the dell and on the high surrounding mountains have been partially explored.
During these investigations we explored around 5km of underground tunnels, although most of these have not been fully explored. In some canyons we saw tens of caves with halls opening on vertical walls, thus we could only reach them through climbing techniques: free and aid climbing, fixed rope ascents.