In a city already formed in its essential traits, with its historic districts of Castello, Stampace, Villanova and Llapola, the Hispanic Monarchy had a great influence on Cagliari urban structure adapting the defenses to the new war needs, exploiting to the most the internal walls space and encouraging the cultivation of extra-moenia areas left in a state of abandonment. Cagliari was a composite city, were the inner integration between Catalans-Aragonese and Sardinians progressively settled and interacted with different ethnicities, as in other urban realities of the Mediterranean frontiers of that time. Through the archive sources (emphyteusis concessions of state property and notarial acts), it is possible to perceive a lively city and locate the sacred and profane places: palaces, streets, squares, fountains, churches and convents are cited as fundamental citizen reference points. The emphyteusis give us an important basic framework which allows us to know both the urban structure and the policy of the Crown at the same time, through the management of the state properties. Notary’s acts integrate these data bringing interesting information on private estates and on architectural characteristics of the realty.