Shortly before km. 16 of the road from Begues to Olesa de Bonesvalls (a few metres before the quarry and cement and lime factory CI Aries), a track (closed) emerges which shortly afterwards crosses the riera de Begues and climbs up the bottom of l'Espinadar. Further on we find on the left the remains of the corrals of els Casals and a little further on, on the right, the ruins of an enormous farmstead (els Casals). The path continues onwards tending to go to the right, until it becomes a footpath (GR-92.3) that climbs the hydrographic slope until reaching a col (some call it the coll de la Ferla). Before it begins to descend towards the Avenc de la Ferla, the footpath goes off to the right and about 50 metres further on turns right, it is here that it must be left and one must continue straight on over the rascler and losing a little height for about 100 metres to find within a space of a few metres the entrances of the cavities (Farigola II; Aranyes Negres and “Grieta”).