The Miróbriga Archaeological Station, classified as a Property of Public Interest since 1940, has been referenced since the 16th century and is located on an elevation with defense structures, in a privileged area of visibility in order to control the territory rich in agricultural resources. , seafarers and miners.

The Site has a Reception and Interpretation Center.

The ruins are located next to the city of Santiago do Cacém and hosted a settlement that emerged during the Late Bronze and Iron Age (6th-1st centuries BC) and remained until the 4th century AD.

The Archaeological Site of Miróbriga is considered the most important after Conímbriga.

In the Roman Period, the space underwent considerable expansion, with the construction of various buildings and housing structures, along the sidewalks and decorations with frescoes.

Miróbriga also had a forum, where a temple was erected, probably dedicated to the imperial cult and another dedicated to Venus. Surrounding the Forum, the commercial area and the other buildings are developed and to the south was the commercial area that had several stores (tabernae) and an inn.

The spas, one of the best preserved in the national territory, are made up of two buildings that are annexed, possibly for male and female use; between the 1st and 2nd centuries AD. the remaining constructions appear – entrance area, changing room and games room and an area for cold baths (frigidarium) and another for hot baths (caldarium and tepidarium).

It also has a single full-arch bridge and the floor, made of limestone slabs, is still the original. The rainwater drainage system is also visible.

Approximately 1 km from the archaeological site of Miróbriga are the ruins of the hippodrome. It measures 370 m by 75 m and was divided in half by the “spina” (ditch) with a goal at each end.

The hippodrome was used for chariot races drawn by two or four horses (bigas/quadrigas) being the only specimen of a fully known plant in the national territory.