Saint Sebastian Fortress

Saint Sebastian Fortress is a military stronghold on Revellin Hill featuring five massive bastions and thick defensive walls that dominate the surrounding landscape. The structure integrates naturally with the terrain through its irregular plan, which maximizes both defense and command of the territory below.

This fortification was constructed in the 17th century as a vital component of the Algarve's defense system against maritime threats. It played a key role in protecting coastal trade routes and controlling access to the region during a period of intense naval activity.

The structure exemplifies Portuguese military engineering techniques through its irregular layout, which adapts to the natural terrain while maintaining defensive capabilities.

The exterior is freely accessible from various points around the site, allowing visitors to view the fortification's architecture and bastions from different angles. Daytime visits work best for appreciating the wall details and views of the landscape below.

The fortress links directly to Castro Marim's medieval castle through its northern entrance, creating a continuous defensive system spanning different periods. Visitors can walk through this connection to experience how military architecture evolved across centuries on the same site.