The ancient origin of the town is attested by the numerous buildings in the area; according to the nuraghi density map, made by prof. Giovanni Lilliu, Genoni is among the areas with a density greater than 0.60 nuraghi per km², most of which can still be visited.
The elevated position of the Santu Antine hill, which Genoni is built on, has certainly attracted populations to settle in this area since ancient times.
Punic, Romans and most likely also the Vandals reached and then chose to live both in the Giara and on the Santu Antine hill; as the ruins found from the different eras allow us to hypothesize.
The walls of a Punic fortress on the hill, and, always at the top of the hill, the ruins of a Roman church dedicated to St. Helena and Constantine.
The villages of Santu Pedru, Mammuzzola, the spectacular Bruncu Suergiu and the sacred well of Sa corona arrubia.
The town reached large dimensions, probably because of its position out of the main transit ways.