Boundary Fortifications
In the west, near the boundary with Portugal, there are different fortifications, due to the wars and fighting that took place throughout the history. Some of them played a very important role during the Napoleonic Wars.
They are medieval constructions reinforced in the 17th and 18th centuries following the bastion fortresses model. If we look at them from above, their star shape, with moats and ravelins really grab our attention.