1,600-Year-Old Christian Basilica Discovered Beneath Italian Fish Market

Surveyors in Oderzo, in the province of Treviso, in Italy, were investigating the area of a former fish market for a construction project. Suddenly, their earth-moving equipment revealed a section of a mosaic tile floor. The site is outside the city walls of ancient Opitergium, an area where prior archaeological excavations have uncovered mosaics, tombs, and a Byzantine fort. Opitergium was originally a 10th-century BC settlement of the ancient Veneti. When Rome built the Via Postumia road in 148 BC, travelers visited the town on their journey from Genoa on the northwest coast to Aquileia on the east coast. In 48 BC, Rome (in fact, Julius Caesar) granted the city “municipium” status with all the rights of a Roman city. Its location at a crossroads helped the city develop rapidly, and the population increased to 50,000 at the end of the 2nd century. More substantial structures, such as a cathedral and a large market area, filled the town’s center. Understanding the need for site preservation, the Superintendency of Padua called in an archaeological team, which began an excavation. Just below street level, they unearthed a large early Christian basilica dating to the 4th and 5th centuries AD. The well-preserved place of worship is a part of Italy’s early Christian legacy, hidden beneath busy streets and shops for 1600 years.

Excavated geometric mosaic floor belonging to a Late Roman/Early Christian basilica discovered beneath the former fish market in Oderzo, Veneto, Italy. (Fine Arts and Landscape for the provinces of Padua, Treviso, and Belluno/Superintendency of Archaeology)

Ornate Mosaic Floors Are a Distinctive Feature of the Basilica

The archaeological excavations that began in November 2025 exposed a large rectangular structure with brick-and-mortar foundations that uses the same support system of wooden piles driven deep into the soil that Veneti homes used in the tenth century BC. There is a three-nave hall, thick perimeter walls, and several burials near the building, all typical of a place of Christian worship. The most distinctive feature of the basilica is the southern aisle. This area has a well-defined perimeter wall, reinforced by buttresses, and an intricate polychrome mosaic floor. A skilled craftsman created the mosaic floor, featuring geometric and floral motifs in colored tiles. One panel of the floor design features a central octagon with a Solomon’s Knot surrounded by an awning motif. Intricate floral decorations with double frames line the sides. Archaeologists have carefully protected the surface so that excavations can continue.

Excavation of human burials associated with the Early Christian basilica beneath the former fish market at Oderzo. (Fine Arts and Landscape for the provinces of Padua, Treviso, and Belluno/Superintendency of Archaeology)

The Oderzo Basilica is Comparable to Aquileia and Concordia Sagittaria.

Four inhumation burials are outside the southern perimeter of the church between the buttresses. The deceased were placed in simple shrouds and buried in the earth without a coffin or other covering. Three of the gravesites are two-person burials. None of them had grave goods. Researchers plan to use radiocarbon dating on the human remains and the wood piles to date the church more precisely. They believe that the Oderzo basilica is comparable to the early Christian basilicas of Aquileia and Concordia Sagittaria. These churches were among the main centers of early Christianity in northeastern Italy. 

Oderzo Has a Significant Place in the Origin of Christianity in the Opitergino Area

Antiquities authorities are currently exploring architectural solutions to make the mosaics and remains of the church accessible to the public. Researchers hope to define the basilica’s size and create a timeline of construction phases. The basilica’s discovery is one of the most important in the Veneto region because of its role in the origins of Christianity in the Opitergino area.

Top Image: Excavated geometric mosaic floor belonging to a Late Roman/Early Christian basilica discovered beneath the former fish market in Oderzo, Veneto, Italy. The church dates to approximately the 4th–5th century AD. Source: Fine Arts and Landscape for the provinces of Padua, Treviso, and Belluno/Superintendency of Archaeology

By Ramsey Hardin

References

Editorial Staff/ La Divina Cultura. 2026. “Exceptional in Oderzo: an early Christian basilica with mosaics emerges.” La Divina Cultura. Av available at: https://www.ladivinacultura.it/eccezionale-a-oderzo-emerge-una-basilica-paleocristiana-con-mosaici/

Heritage Daily. 2026. “Ancient basilica found beneath former fish market.” Heritage Daily. https://www.heritagedaily.com/2026/07/ancient-basilica-found-beneath-former-fish-market/158508

The History Blog. 2026. “Early Christian church found under fish market.” The History Blog. https://www.thehistoryblog.com/archives/76458

Margolis, Andrea. 2026. “Significant early Christian church emerges beneath former fish market in ancient city.” Fox News. https://www.foxnews.com/travel/significant-early-christian-church-emerges-former-fish-market-ancient-city