Sant’Antioco Martire, Minor basilica in Sant'Antioco, Italy

Sant'Antioco Martire is a small basilica in Sant'Antioco on Sardinia with roots in late antiquity. The building shows Byzantine features and hides beneath it an underground network of burial chambers and sacred spaces.

Built between the late 5th and early 6th century as a Greek-cross martyrium over the tomb of Saint Antiochus, who died in 127, it served as cathedral of the diocese of Sulci. In 1089 Benedictine monks from Marseille lengthened the nave into a Latin cross, added an apse and reoriented the church east; it was reconsecrated in 1102. A 20th-century storm exposed its Byzantine origin, long mistaken for an 11th-century building.

The martyr Antiochus, buried here in 127 AD, gave the island its name from the 12th century onward. In 1089 Benedictine monks from Marseille were sent to bring the cult into line with the Western Church, and the church was reconsecrated in 1102. The neobaroque facade and the bell tower beside it date from the 18th-century remodelling.

The church stands in the centre of Sant'Antioco, a short walk from the town's waterfront. The 2019 restoration raised the floor and replaced the altar and ambo in white Orosei marble, and added a new sacristy on the right side; the building reopened for worship on 1 August 2020 after about eighteen months of work.

The church was long dated to the 11th or 12th century; only when a downpour detached part of the plaster in the second half of the 20th century and the parish priest Salvatore Armeni stripped the Baroque furnishings did its late antique origin emerge. The building was re-consecrated in 1102 after the Benedictine monks sent in 1089 reoriented it east.