With a Neolithic site, one Nuraghe and two churches, this archaeological-artistic complex is enclosed in the space of a few tens of meters. Around the Nuraghe Arresi arose the first inhabited nucleus of Sant'Anna Arresi, a village in the lower Sulcis area whose name combines its prehistoric origin to the patron saint, to whom are dedicated ‘old’ and new parish. The Nuraghe, dating from the 15th-14th century BC (Middle Bronze Age), stands between the two churches and was built on an older settlement, inhabited in the late Neolithic and the early Aeneolithic periods (3200-2600 BC). Completing the prehistoric picture within the village are two Nuragic fountains, to the east and west of the monument. It is a case of cultural superimposition: various spiritual ‘forts’ came in succession within the town for millennia.

Arresi is a Nuraghe ‘a tancato’, which consists of a main tower connected to a secondary wall via two arms that close to form a courtyard. The building is made of limestone blocks arranged in rows with irregular ‘weaving’. The main tower (keep) has a diameter of about 13 metres and today is seven metres high today, whilst the secondary tower is smaller, having a diameter of four metres and a remaining height of two and a half metres. The entrance is in the arm of the eastern wall, surmounted by a granite architrave and leading into a hall in whose walls open up two small rooms. The corridor leads to the inner courtyard overlooked by the two towers. Inside the keep, travelling along a corridor, there is a small blind room and a narrow and steep staircase. Inside the main room are three niches arranged in a cross formation. In the secondary tower, there is a small room and an adjoining niche. No traces of a terrace or of the tholos roofing of the towers remain. The complex gives its name to the square in which it stands, Piazza del Nuraghe. It is here, at the beginning of September, that one of the most famous and long-lived Sardinian music festivals takes place, being Ai Confini Tra Sardegna e Jazz.

Other Nuragic structures and Tombs of Giants are scattered throughout the Sant'Anna territory. Along the road that leads to the beautiful Porto Pino - including four kilometres of fine white sand, surrounded by lagoons and pine forests - there is the Coi Casu complex, inhabited between the late and final Bronze age (17th-11th century BC). It consists of a Nuraghe complex with a village, around which emerge the ruins preserved by the lush Mediterranean vegetation. Amongst the various structures is a space for preserving food. Life returned to the settlement in the late Punic period (3rd-2nd century BC) until the Byzantine period (7th century AD).