On the hill overlooking the basilica of Sant’Antioco is the Savoy fort called “Su Pisu.” It was built between 1813 and 1815 to provide shelter for the soldiers and population of Sant’Antioco in case of siege by Saracen pirates. Following the tragic raid of July 22, 1812, the people of Sant’Antioco had strongly urged the Savoy government to take steps to defend the community. Queen Maria Theresa granted a grant of 700 scudi for the construction of the fort. After long vicissitudes, the fort was finally finished in the summer of 1815. New commander was appointed artillery second lieutenant Efisio Melis Alagna, who had Sardinian artillerymen under his orders. On Sunday, October 15, 1815, at sunset, a fleet of about 15 ships appeared in front of the shores of the island of Sant’Antioco, alarming the population; the commander saw that the ships were flying the British flag. Efisio Melis Alagna did not notice that the ships had arrived from Tunis. On October 16, 1815, at about seven o’clock in the morning a thousand privateers, aboard their lifeboats, stormed the beaches of “Su Pruini (present Is Pruinis)” and “Sa Punta De S’aliga,” then headed for the town. The panicked residents of Sant’Antioco abandoned their homes and fled to the countryside. The commander and 16 soldiers took refuge in the fort with a small part of the population and among them even Angelina, Efisio’s sister. The Tunisian commander arrived with his army at the foot of the fort nor ordered the assault. The assaults continued for about seven hours, but the defensive bulwark seemed impregnable. The Tunisians, having penetrated the fort took the defenders by surprise. The fight, however, soon turned out to be unequal, so much so that, the soldiers who escaped the fight and the civilians in the fort surrendered. Commander Melis and 10 of his men were killed in the clash. Six soldiers surrendered into the hands of the attackers. Efisio Melis Alagna’s sister and other women were captured and taken prisoner to Tunis. There were 133 people captured in Sant’Antioco. The garrison commander, Efisio Melis Alagna, was buried in the church of Sant’Antioco and, in memory of the sacrifice, honored with a memorial inscription.