The origin of Santiago do Cacem remounts to pre-history, as it was attested by the archaeological researches in Castelo Velho, at the top of a hill, east of the borough, where you find the Roman ruins of Mirobriga. That village from the end of neolithic was lather fortified by the Celts and in the 3rd and 2nd century BC. This land is a blend of maritime coast, pine forest and Alentejan inspiration. It is the country's second biggest municipality and its highest elevation is to be found in the Cercal hills at a height of 346 meters. From here one can see the vastness of the sea to the West.