The region of the Site of Community Importance “Giara di Gesturi” is characterized by the relations that bind the highlands of volcanic origin (the giaras, which are the dominant geomorphological elements in the area) and the system of hills dating back to the Miocene epoch, which is composed of flat areas and rounded ridges. The hilly landscape of the region, marked by the valley of the Flumini Mannu River, stretches around the giaras of Gesturi, Serri, and Siddi.
The predominant soils of the marl and sandstone areas are evenly distributed according to a variable sequence from the bottom of the valley to the summit of the mountains, giving the area a greater susceptibility to agricultural use in floodplains. This distribution extends until the system of the Campidano plain.
The local agricultural system, conditioned by numerous non-irrigated areas, has historically followed a dryland farming model, especially for cereal cultivation during the autumn-winter cycle. A local peculiarity is the spread of non-irrigated areas covered by olive groves and crops, which are usually placed on hillsides or ridges near towns and are often grown for family consumption or for the local economy.
Although affected by marginal agricultural practices, the reliefs have had a strategic role since the beginning of the settlement processes because the natural drainage of the land and the weather conditions have given the hilly area irregular features, which are risky for monocultures. As a result, the fate of each individual farmer is closely interwoven with that of the agrarian community, favoring both the wide spatial dispersion and the self-containment of the towns.
These settlement trends are related to both the dynamics of agricultural land and the preservation of the the pedological resource and have resulted in a dense and minute urban setting composed of a network of small rural towns.
The topography has also promoted relations between communities since ancient times. This is evidenced by the many archaeological sites dating back to the Nuragic era, which are part of the cultural and historical heritage of the region.