Since the nearly 4.5 kilometers of the old railway track, built at the end of the 19th century along the slopes of these limestone-dolomitic mountains to transport minerals, can no longer be used, we walk along the valley floor until we enter the forest. A dirt road or a path leads us to the Case Marganai, in a beautiful mountain environment, where it is possible to visit the Linasia garden. Mining activities have left important traces here, immersed in lush nature. Almost 800 meters are traveled underground, crossing from north to south the second largest karst cavity in Europe accessible to trucks, now open only to pedestrians, horse riders, and cyclists. Also remarkable is the nuragic site of Sa Domu ’e S’Orku. The steep descents from Case Marganai along the mule track switchbacks require particular caution.

WARNING: To cross the Grotta di San Giovanni, it is necessary to go to the north entrance, ring the bell, and identify yourself as a CMSB pilgrim; an operator will come to open. The cave is open from 9:00 a.m. to 6:00 p.m. and an entrance fee of 5 euros is required; otherwise, there is an alternative route available outside.