The Aragonese age marks a moment of profound transformation of the urban layout of the city of Taranto. In these years, in fact, important reorganization works of urban spaces were started which aimed at improving their defense. Probably under the pressure of the various sieges and above all the Turkish threat, important restoration works of the ancient castle began and were entrusted to the Sienese architect Francesco di Giorgio Martini.

It will be thanks to these modernization and military efficiency works that the ancient Byzantine fortress took on a shape very similar to the current one. In fact, during these years, the excavation of a deep moat began in the area now occupied by the navigable canal, which significantly changed the state of the places, transforming the Old City of Taranto into an island in all respects. In the same years, works began to rearrange the ancient tower built by Raimondello Orsini del Balzo in the Piazza Fontana area to make Porta Napoli safer.

The view of the city on the Great Sea, naturally defended by the jump in altitude, on which the Greek walls of the Taranto polis had been grafted in ancient times, was made more efficient from a military point of view thanks to a series of tense consolidation and reorganization works. to improve the military response and ensure greater defense of the urban center. To cope with the huge economic expense, it was decided to divide the costs relating to the defense works of the city. The Royal Government took charge of the construction of the new castle and the excavation of the moat, while the University was responsible for paying for the construction of the new walls and garrison towers. Over time, the fortification works proved to be extremely onerous and with very long execution times. In 1484, in fact, the construction of a single tower (that of Sant’Angelo) was completed, erected at the expense of the Taranto inhabitants.