The Pisan tower of San Pancrazio was designed by architect Giovanni Capula in the early 14th century to defend the northern entrance to the castle. Built of limestone at the highest point of the hill, from its summit, more than 130 meters above sea level, it was possible to control the territory surrounding the city. In 1328 the open side was plugged by the Aragonese to turn the building partly into housing for officials, and partly into a warehouse. From 1600, with the opening of the passage into the adjoining Palazzo delle Seziate, the tower lost its function as an entrance to the city, and was used as a prison until the late 1800s. In the early 20th century it was restored to its original condition, with the reopening of the side facing Independence Square, and the restoration of the wooden galleries. A recent restoration reinforced its structures and rediscovered part of the defensive apparatus. Together with its twin Tower of the Elephant, it is one of the few medieval buildings in Cagliari that have been preserved almost intact. Various defensive solutions are worth highlighting, such as the several loopholes facing various heights, the traces of the numerous barrages of the gate below, including two portcullises and three portals, and finally, at the top, the crowning of corbels from which any attackers could be bombarded. The tower was surrounded by a wall called a “barbican,” beyond which was a moat. At various heights on the north side are walled Pisan coats of arms, while on the archway of the gate, on the opposite side, is a Latin inscription recalling the Pisan castellans of Cagliari at the time of its construction, the contractor who carried out the work, and the architect designer Giovanni Capula.
