Excavated in an amphitheatre of trachytic rock on the southern side of the ‘silent’ hill of Sa Pranedda, it consists in over 40 tombs of various sizes and has a layout aligned along the rock face in a symmetrical way, according to a design that seems to have been pre-planned. The necropolis of Montessu is one of the most significant and fascinating pre-Nuragic remnants on the island, in use for a millennium and a half, from the final Neolithic (3200-2800 BC) to the ancient Bronze Age (1800-1600 BC), as evidenced by the ceramic finds discovered and safeguarded in the archaeological museums of Cagliari and Santadi. The sheer size of the prehistoric burial ground dominates the Rio Palmas plain boarding the village of Villaperuccio in the lower Sulcis. In addition to the necropolis, the valley is home to an archaeological park including an allèe couverte, two Nuragic structures and two imposing menhirs reaching around five metres in height. The necropolis headed a village in the 3rd millennium BC, the remains of which can be seen on the hill of s'Arriorxu. Many other perdas fittas (driven into the ground) characterise the territory, where there is another Neolithic necropolis, the Domus di Marchianna, and the ruins of 40 other Nuragic structures.