The Romans founded the civitas of Aeminium in this place at the time of Augustus, which came under the protection of nearby Conímbriga situated some 15 kilometres (9.3 mi) to the south.

An aqueduct existed, the remains of which were incorporated into a latter medieval renovation.

Locations for the theater and amphitheater were also proposed, but still unconfirmed by archeology.

The most important is the cryptoporticus, an underground gallery of arched corridors built in the 1st or 2nd century AD to support the forum of the city.

[2] During the Middle Ages the bishop's palace, now turned into the Machado de Castro National Museum, was built over the forum; the cryptoporticus is located under it.