The Marquis of Quirra ordered its construction in 1582, following a heavy raid by North African pirates in 1577. The tower, named 'Castellas de Pula', was completed in 1589 to defend the surrounding coastline: its line of sight reached the towers of Cala d'Ostia, San Macario and Diavolo.

It was a tower 'de armas' and was inhabited by a commander, a gunner and four soldiers. In the mid-1700s, the structure was transformed into a proper military fort, based on a project by engineer Antonio Felice de Vincenti. The summit was enclosed with a square wall, with patrol trenches and small turrets at the corners.

Inside this wall, at the foot of the tower, cannons faced the open sea. After the closure of the Tower Management Board s in the mid-19^th century, it was turned into the semaphore station for Cape Pula.

The building measures 11 metres in height, while the entrance is approximately halfway through – with a modern masonry staircase now outside to facilitate entry. The main chamber has a domed vault with a central pillar, while other indoor facilities include the commander's room, the soldiers' quarters, the ammunition depot, storerooms, the galley and the kitchen.