Sant'Antioco (; ) is a town and municipality on the island of the same name in southwestern Sardinia, in the Province of Sulcis Iglesiente, in the Sulcis subregion. With a population of 10,451, the municipality of Sant'Antioco is the island's largest settlement. or Solki, of which a tophet (children) necropolis has been excavated. Later (6th century BC) it became a Carthaginian colony, to which another necropolis belongs. The Punic domination ended in the 3rd century BC, when Sulky was conquered by the Romans, who connected it to the mainland through an artificial isthmus. During the civil war between Julius Caesar and Pompey it sided with the latter, being severely punished after his defeat. During Roman times, it was called Plumbaria, after its lead deposits.
The current city name derives from St. Antiochus, evangelizer of the area, who was martyred in 125 AD. After the decline and the end of the Western Roman Empire, Sant'Antioco was a fortified strong point of the Byzantines. It was repeatedly attacked by the Saracens starting from the early 8th century, and gradually abandoned by the inhabitants who fled to the more protected inner area; the island mainly remained important as the end of pilgrimages devoted to St. Antiochus. A new settlement (bidda in Sardinian) was established around 935 by the judge (the local title for lord) of Cagliari, but this also was abandoned after the end of the giudicato. The island was a territory of the Kingdom of Sardinia (created in 1324) and later was acquired by archbishopric of Cagliari (1503) and, in 1758, by the religious Order of SS. Maurizio and Lazzaro. In the 18th century the area began to be repopulated and toward the mid of the century there were 38 houses, 15 workshops, and 164 huts, with some 450 inhabitants.
thumb|Forte of Su Pisu, 1813-15
In January–May 1793 the island was occupied by French troops under admiral Laurent Jean François Truguet, and the citizens freed from ecclesiastical taxes. The last attack by North African pirates occurred in 1815; the same year in which the relics of the patron saint were brought back to the cathedral.
Climate
Demographics
As of 2025, the municipality has a population of 10,451, of whom 49.1% are male and 50.9% are female. Minors make up 10.7% of the population, and seniors make up 32.5%, compared to the Italian average of 14.9% and 24.7% respectively.
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|+Foreign population by country of birth (2024)