The small church of San Proto, which houses the stone tombs of the saints Crisogono and Proto, was partially investigated in 1960-61 by Mario Mirabella Roberti, professor of Christian Archaeology at Trieste University. The results were notable and brought to light the structures of a small aula, datable to the 4th century A.D. This structure housed the cult of one of the martyrs from Aquileia killed during Diocletian’s persecutions in 304 A.D., that is San Proto who was the pedagogue of the three brothers Canzio, Canziano and Canzianilla. The basilica which was built in the area of the present parish church was dedicated to them. The basilica was also excavated by Mirabella Roberti in the 1960s.

At San Proto, Mirabella Roberti’s investigations were preceded by those of an orthodox priest, father Timotheos, who in 1950 had conducted excavations, unfortunately badly documented, in the area outside the church. He brought to light a mosaic pavement which was later in date (5th century) than that uncovered by Mirabella Roberti. Therefore, this is an area of great historical and archaeological interest, not only for the Early Christian remains but also for those of Roman date that have been repeatedly noted in this zone, which is thought to be adjacent to the ancient road from Aquileia to Trieste.

The excavations were concentrated in the central part of the building and uncovered a series of floors relating to the late medieval church, in relation to which without grave goods were identified. One was a male individual buried in an earth grave whose position in the central part of the church denotes privilege. Beside this was the earth grave of a newborn baby, placed inside a cup with another cup used as a lid. A further two burials belonged to this same late medieval funerary context, identified by the 1960s excavations, but only investigated during this campaign. Of the two graves, aligned along the south perimeter, only one contained an articulated skeleton. This was a female individual, buried inside a wooden coffin, with a cloth band on the head and circular iron shoe buckles, an accessory in use between the 14th and 16th century.