The Castro de S. Lourenço is a fortified settlement, dating back from the 4th century B.C.
Since the 2nd century B.C., homes were built in terraces all over the mountain. The excavated area showed the existence of housing units, which are often surrounded by a granite pavement. Three walls assure the inhabitants’ protection.
The end of the 1st century B.C. witnessed several changes that lasted until the 4th century. A.D., bearing witness of the Romanization process.
After an abandonment period, a defensive system – a type of small castle was built around the 14th century in S. Lourenço Mountain.