The basilica was constructed directly atop an ancient Roman burial ground, with over 400 tombs discovered during excavations.
The granite used for the construction was quarried from the surrounding Gallura region.
Saint Simplicus, to whom the basilica is dedicated, was the Bishop of Fausania and was martyred in 304 AD.
The structure displays an unusual lack of decorative sculpture on its exterior, adhering to the austere style of Pisan Romanesque architecture.
A collection of archaeological finds from the site is housed in a dedicated museum space nearby.
The building's floor plan is a classic Latin cross, though it lacks a traditional transept.
The Basilica di San Simplicio is the oldest and most important religious monument in Olbia, Sardinia, dating back to the 11th and 12th centuries. Built entirely in local grey granite, it represents one of the finest examples of Romanesque architecture on the island. The interior features a three-aisled plan with a semi-circular apse and walls composed of exposed stone blocks. Beneath the altar lie the relics of Saint Simplicus, the patron saint of Olbia and a martyr from the Diocletian persecution. Recent archaeological excavations have revealed a Roman necropolis directly beneath the church floor. Visitors can view fragments of medieval frescoes depicting the saint and various apostles. The site underwent significant restoration work in the early 21st century to reinforce the structure and preserve its historical integrity. It remains an active parish church serving the local Olbia community.
From the Piazza S. Simplicio looking up at the main portal to capture the symmetrical Romanesque facade.
Visit the adjacent archaeological museum area to see artifacts recovered from the Roman tombs beneath the basilica.
Check the local parish calendar as the basilica often hosts weddings or funeral services that may restrict tourist access to the nave.
Walk around the exterior to see the transition of masonry styles from the 11th-century original core to later additions.
Do not enter if a liturgical celebration is in progress; avoid taking flash photography near the altar area.
May be closed to tourists during private religious ceremonies, baptisms, or funerals.
Shoulders and knees must be covered; maintain a quiet tone as this is an active place of worship.
