The catalog of the exhibition held from 21 June to 2 October 2017 at Casa Buonarroti (Florence) is dedicated to the biennium of 1529-1530, when the Republic of Florece was besieged by the Imperial troops of Charles V. Michelangelo Buonarroti, who was a skilled military architect, was charged to strengthen the city defenses. The book focuses on twenty original drawings by Michealngelo showing the main fortification plans designed to reinforce different points of the walls.