Torre di Porto Giunco, Spanish defensive tower on Cape Carbonara, Italy.

Torre di Porto Giunco is a granite coastal tower on Cape Carbonara, on the southern tip of Sardinia, Italy. It stands on a rocky promontory above the sea, with water visible on several sides and the coast stretching behind it.

The tower was probably built in 1578 as one of the coastal watchtowers the Spanish crown raised between the 16th and 17th centuries along southern Sardinia to spot Barbary pirate raids. Each tower could see the one before and after it, letting signals travel along the coast. Abandoned in 1721, it was back in service by 1758 and withstood a Tunisian fleet in 1812; it was still listed as active in 1843.

The tower belongs to a chain of coastal watchtowers built by the Spanish between the 16th and 17th centuries along the coasts of southern Sardinia. Each tower was placed so that the previous and next one were visible, allowing fast communication along the coast with lights and signals. Coming from Cagliari, the towers are encountered in order: Cala Regina, De su Fenogu, Capo Boi, the old fortress of Villasimius, Isola dei Cavoli, Porto Giunco, Serpentara and Cala Pira.

The tower is reached on foot from Porto Giunco beach along a path that starts flat and then climbs to the cape. The site is open and exposed, so sturdy footwear and sun protection are worth having before you set off.

The tower is one of the senzillas, the medium-sized class of Spanish coastal watchtowers, and each tower in the chain could see the one before and after it, so signals sent with lights could travel along the whole coast. From Porto Giunco the next towers in the line are those of Serpentara and Cala Pira.