Form and Project of Modern Age Fortifications. The case of the city walls of Pisa

The fortification “a la moderna” of Pisa in the Modern Age was not made, as in other Tuscan cities, with the construction of a new bastioned front, but strengthening the pre-existing medieval walls. The construction of the new front was developed between the 16th and 17th century in two different phases. In the first phase, starting from the mid-16th century, a few of small bastions were built in some strategic points of the medieval circuit. Only in the first half of the 17th century, the defense system was completed by the military engineer Gabriello Ughi, with demilunes and outworks in earth. The new defense system, demolished in the late 18th century, is described only in a series of historical maps and archival documents. This paper therefore aims at proposing the first results of a study on the 17th century fortification project, starting from a graphical analysis of the historical maps, in order to understand the design choices in the light of the progress of defense techniques at that time and of the constraints determined by the pre-existing structures and the orographic context