The Longue Durée of the Borgo Fortifications Available to Purchase

The dominance of civil architectural paradigms in the analysis of the design of the Vatican Borgo fortifications, including the Castel Sant’Angelo, has generated a scholarly narrative that focuses on the design decisions of individual architects. However, such an approach cannot adequately address the complexity of a large-scale military project with unique site-based limitations. In The Longue Durée of the Borgo Fortifications, Ian Verstegen presents the fortification of the Borgo as a collective, military problem, where the site dictated the solution. Through a review of payments and drawings, this essay reveals that the majority of work occurred under Paul III and his engineers, Antonio da Sangallo the Younger, and Giacomo Fusti Castriotto, who not only determined most of the Borgo’s design but also concluded trenchwork much earlier than previously supposed. Moreover, rather than focusing on individual designers, the article underscores the importance of military engineering site requirements and the contributions of anonymous soldiers to this project.