Torregiana
The defense system called Torregiana was installed by the Genoese , completing the Pisan beginnings, from the middle of the 15th century along the coast of Corsica . 150 round crenellated watchtowers were built within sight of each other . 67 of them are intact or in ruins. The mostly four-story towers were designed to prevent pirate attacks , which Corsica was exposed to for centuries.
In 1453, the Genoese St. George's Bank, to which the Ligurian trading city of Genoa had been in debt for half a century, took over the island as pledge from Doge Pietro di Campofregoso and installed the noble Antonio Spinola as the first governor. While the Pisans had mainly built churches and chapels, the Genoese were characterized by the construction of citadels, watchtowers and bridges.
After a few years, 150 of the towers between 12 and 17 m high existed. The square ones (in Nonza , Morsiglia , Pino, Porto and Toga) are of Pisan origin. For their part, the Corsican notables had square towers built, which served as a dwelling and, in case of danger, as a refuge. The round towers, about 7 m in diameter, are Genoese. The towers, slightly tapered at the bottom, were manned by four men. As soon as a Saracen sail appeared on the horizon, the guards lit fires on the platforms and the residents fled into the hinterland.