For centuries, the coastal tower complex of Sardinia was one of the island's main defence systems, enabling lookouts to spot enemies arriving from the sea.

Arab raids of the Sardinian coasts began in the first years of the VIII century A.D. and continued for the following decades. So much so that they had to build the first coastal defence towers.

From the IX to the XV century, during the Sardinian Giudicati period (Cagliari, Arborea, Torres and Gallura) and the dominion by Pisa and Genoa, several forts were built. When Spanish dominion of the island began, there were about sixty towers guarding the Sardinian coasts.

At the beginning and for the entire first half of the XVI century, raids increased considerably, causing dismay and destruction not just for the coastal populations in Sardinia, but also for southern Italy and Spain. At the start of the century, the moriscos expelled from Spain were welcomed by the Berber people dedicated to piracy and the slave trade and the proximity of Sardinia to North Africa exposed it to the attacks of Turkish-Barbarian pirates. So much so, that the Spanish Crown studied opportune counter-measures to maintain control of the island.

As early as 1570, they began designing a network of fortresses to defend the coast. But it was only in 1587, following a raid of villages near Cagliari in 1582, that King Philip II of Spain set up the "Royal Administration of Towers", assigning it the task to build new towers, manage them, enlist soldiers and provide them with weapons (fig. 1). This body, with its headquarters in Cagliari, was headed by the Viceroy who appointed a captain (alcaide), gunners and soldiers to defend the tower (fig. 2). Their task was to monitor the sea continuously to spot enemy vessels and sink them using canons.

Fig. 1 - Stone placed on the facade of the Royal Palace in Cagliari in memory of the "Royal Administration of the Towers" (photo M.G. Arru).

Fig. 2 - Model of a soldier (Museum of the towers of Sardinia).

The pirate phenomenon stopped at the start of the XIX century so the coastal towers were no longer needed. The Royal Administration of Towers was suppressed in 1842. However, some of the towers that were still manned were used for military purposes; as a seat for signalling and lookout systems and were only decommissioned in 1989 with a State-Region agreement.

In general, the towers were positioned at strategic points from where you could cover wide stretches of sea and each tower could communicate, by luminous signals, with the ones next to it.
Almost all the towers are circular and conical or cylindrical (fig. 3) and can be divided into three types:

• de armas or gagliarde, that is the bigger towers, seeing as how they were on average about 17 metres in diameter and 14 metres high; they were under the command of an alcaide, with a gunner and four soldiers under him. Weapons were four large canons, two mortars and five rifles.
• senzillas, medium sized towers (13 metres in diameter and 10 in height); they were manned by an alcaide, a gunner and two or three soldiers and had two medium-caliber guns, two mortars and five rifles.
• torrezillas, the smallest (5 metres in diameter and 7 in height) and almost only lookout posts. They were manned by two soldiers armed with a mortar and two rifles.

Fig. 3 - Model of a coastal tower (Museum of the towers of Sardinia).

The tower entrance, about 4-6 metres above ground, was accessible by a rope or wooden ladder which, after use, was hoisted inside. On the terrace, called the place-of-arms, the soldiers performed their lookout, guard, signalling and artillery fire duties (fig. 4). This was reached through a trapdoor with a rope ladder or by brick stairs dug in the wall or built onto it.

Fig. 4 - Model of a coastal tower: the place-of-arms (Muesuem of towers of Sardinia).