In 181 B.C. the colony of Aquileia was founded, a first-rate base for Roman expansion eastwards, as the conquest of Istria a few years later (178-177 B.C.) attests.
The Muggia territory, having entered the orbit of the Roman state, was thus subject to a centralised power which guaranteed a certain social tranquillity and steady commercial activity: remains of maritime equipment are still visible along the Muggia coast, as for instance the Stramare Pier.
The human settlement on the hill of Muggia Vecchia has left a whole series of scattered tracks, for the most part associated with the Basilica of Our Lady of the Assumption. Future discoveries, hopefully, will determine the exact nature of the site; for the present the doubt remains as to whether we are dealing with a rural residence or a military site. The presence of burial remains leads one to suppose the existence of a funerary area.
A range of materials have been preserved from the Roman phase, such as the Roman funerary altar dedicated to the eighteen-year-old C. Iulius Nicostratus by his parents – reused inside the Basilica as the base of the altar in the left hand aisle – and the sarcophagus placed on the grass behind the Basilica. A number of amphorae were used as building material to lighten the vaulting of the apsidal recess. Under the main altar, instead, was found a Corinthian capital of the C1st-C2nd A.D., and in a grave in the cemetery a bronze coin was found, an as struck by Tiberius in honour of Augustus in A.D. 15-16.
Other objects are coming to light at various points in the park. There is a curiosity: a modern sundial set into an external wall of the presbytery records how here in 1923 was found a Roman sundial formed out of a block of limestone. The original sundial is currently preserved in the Muggia Archaeological Museum together with the Corinthian capital.