The term "giare" refers to a few basaltic highlands in Sardinia, formed during the Oligocene period by volcanic phenomena, characterized by very steep escarpments within the Marmilla and Sarcidano territories. There are three altogether, Gesturi, Serri and Siddi. The Giara di Serri reaches 650 m above sea level, is 3 km long and 1.4 km wide. The name (that Wagner connected to the Palaeo-Sardinian substratum) some say derived from the Catalan "haras", indicating by this term the place in which herds of horses live. But the exceptionality of the giare is not limited to their geomorphologic and flora-faunistic aspects. The view that can be enjoyed from these highlands from their vertical walls stretches from the massif of the Gennargentu to the lowlands of the Campidano, and from the Marmilla, with its characteristic gentle hills, to the sea in the distance on clearer days. Most spectacular is the archaeological complex on the Giara di Serri that preserves a Nuragic sanctuary that takes the name of Santa Vittoria from the nearby church, and covers around 3 hectares and a half near the south-western escarpment of the Giara. It is a large area that includes buildings of various function but all pertinent to the sanctuary. The complex is made up of four main structural groups: the two temples (a well and open layout), the priest's hut with its annexes, the enclosure of the feasts and the group made up of the enclosure of the double bethel and by the east-southeast enclosure. One of the greatest and representative lay-outs are the so-called "enclosure of reunions" or "of the feasts", a vast enclosed elliptical area, around 75 m long on its longest side. The hypothesis is that it was used for the reunions of the nearby tribes and to carry out communal celebrations and hold inter-cantonal markets.