At the bottom of an opening made by desobstruction, a crawlway leads to a series of consecutive pits of 12, 16 and 14 metres (level – 45). Here, a very narrow passage communicates with a pit of almost 17 metres divided into two routes that reach the same bottom. In a corner of the base of the pit, another crawlway leads to a conduit that communicates with a chimney and with a point where the narrowness makes it impracticable at – 66 metres.