In 1548, under the Florentine lordship of the Medici, Charles V gave Cosimo I de Medici the task of defending the territories of Elba and the commercial traffic of the Tyrrhenian Sea. The Duke, who strongly believed in the potential of the island and wanted to transform it into the center of Florentine rule over the Tyrrhenian, decided to fortify the ancient city of Ferraia, the current Portoferraio.
The objective of this research is regarding the construction techniques used in the military architecture of Cittadella-Fortezza (Ancona, Marche, Italy). In this case, attention will focus primarily on historical, bibliographic and archive research, then through a comprehensive analysis of building methods used in the sixteenth century and on the strategic function that this fortification covered in the coastal strip of the Middle Adriatic.
In the fifteenth century, the Mediterranean world was in turmoil. A new sultan, Mehmet II, had just inherited a vast empire stretching over two continents in the centre of which the ruins of the Byzantine Empire survived through the city of Constantinople. In order to seal his accession, he therefore undertook important preparations to conquer the “City guarded by God”. Mehmet then ordered the construction, within 4 months, of an imposing fortress nicknamed Boǧazkesen (the throat cutter).
In the Ottoman regency, the fortifications of Algiers evolve according to the politico-economic growth experienced by the city partly thanks to the development of the maritime piracy and the lusts it entails. Its stranglehold on the sea, arouses many projects of punitive expeditions. The construction of fortifications is then the major concern of its new leaders who between the sixteenth and the seventeenth centuries, fortify the city, its bay and the hinterland.
Starting from the fifteenth century, the diagram of many fortresses has a pentagonal shape. Among the best known fortresses, in Italy we find the Fortezza da Basso of Florence, the Cittadella of Parma, the Cittadella of Turin, Castel Sant’Angelo in Rome.
The aim of this article is to analyze the reasons that link form and geometry to the planning of the design and the layout of pentagonal fortresses.
In the summer of 1502, Cesare Borgia appointed Leonardo da Vinci for his engineering expertise. His assignment was specific and concerning with military architecture: he was expected to “see, measure and do good estimation”. The Codex L, a small notebook conserved in the Library of the Institute of France, show the results of the survey of the city walls of Cesena and Urbino.
Even in the defensive and fortifying processes, two aspects can be found: the material component and the immaterial one. If all the constructive, material and structural procedures are the first, for example, all that concerns remote communications (maximum optics) belongs to the second, an indispensable tool to complete an optimal strategy for offensive and/or defensive operations.