Santa Barbara Fortress, Pistoia

The Fortress of Santa Barbara is a 14th-century urban castle erected to house troops guarding the town of Pistoia, in the region of Tuscany, Italy. While it is suggested that initially the fortress was named after a nearby church of Saint Barnabas, however, Saint Barbara is the patron saint of artillerymen.

The initial fortress was erected in 1331, after the Florentine Republic had defeated the forces of Castruccio Castracani, and reconsolidated their power over Pistoia. In 1531, under the designs of Nanni Unghero, the fortress was enlarged, but subsequently during the rule of the Grand Duke Cosimo I de' Medici the fortress was further enhanced, initially by Giovanni Battista Belluci, and subsequently by construction of a perimeter wall under the design of Bernardo Buontalenti.

Source: Wikipedia