It is an isolated mountain, nestled in a plain, its walls adopting a strange, almost perfect, U-shaped formation that surprises the visitor. This place has served as the setting for filming several films, The Mummy being the best known. The main wall was built at the beginning of the 19th century, and black slaves brought from sub-Saharan Africa were used to build it, and later sold in Portugal. There is a track that runs through it, inside, up the left wall of the mountain to its top, where there is a small viewpoint. At this point, you can see spectacular views of the surrounding landscape and take some photographs.