The panoramic position of the castle of San Michele is accompanied by its historical importance, qualifying it as one of the most significant monuments of the city of Cagliari. Tradition has it that the castle was built in the twelfth century and strengthened in the thirteenth century, to defend the capital of the kingdom of Cagliari, Santa Igia. In 1324 King James II the Just granted to one of his nobles, Berengario Carròs, the villa of Sinnai in feud, with the promise by Carròs to build the castle of San Michele with the money coming from the donation.
