Trancoso Keep-Tower was built in mid-10th century, with a slight pyramidal shape. In its upper level entrance door we can find a horseshoe arch, a feature of Christian-Mozarabic art that shared many Islamic architecture traits.
Cimo da Vila Tower, surrounded by a simple square shaped wall, similar to Covarrubias tower in Burgos. Example of early defensive structures in Christian territories during the Asturian-Leonese period.
Dating from the 9th century, Lanhoso Castle was rebuilt in the late 11th century during a transition period between proto and full Romanesque with one of its original tower made as a keep.
Penela Castle, standing on huge boulders at the top of a granitic hill, was built after 1087 AD. Its name reflects the nomenclature of this type of castle, called penellas in Latin. In the Romanesque period this tower of this castle was surrounded by an enclosing wall.
Lousã Castle is one of the fortresses belonging to the defensive ring protecting the city of Coimbra in central Portugal. This 11th century castle presents some curious features, such as the round towers that are often to be found in structures of later periods or the irregular ‘fish scale’ stone pattern.
Soure Castle is a border fortress near the Mondego region, that was built in late 10th or early 11th century. It was constructed on top of an earlier Roman or Muslim defensive structure, and it has typical Mozarabic architectural features. The Knights Templar added a keep tower in mid-12th century.
Pena de Aguiar Castle is an old castle-rock that later rebuilt during the Romanesque period. Dominated by two towers, one to the north, connected by a semi-circular curtain and the other to the southeast. In the west wall of this second tower there is a door linked to a smaller barbican shouldering large boulders.
Sernancelhe Castle was built at the southern end of the Douro river, next to the Serra da Lapa. During the 10th century this castle controlled the road between Guarda and Lamego, as well as the course of river Távora. Some remains of the western wall can still be visible close to the ‘Bishop’s House’.
The original wooden fortress of Baião Castle, a feudal stronghold, was destroyed by fire sometime in the early 11th century. It is not certain if the fire was deliberate so as to build something new, or the result of an enemy attack, as could be suggested by the arrowheads and spurs found on site. In any case, a new stone castle, whose ruins still exist, was erected sometime in the late 11th or early 12th centuries.
Castro of Curalha, inhabited from the Iron Age to Late Antiquity, was repopulated and converted into a fortified village at the time of Count Odoário, a local lord responsible for the conquest of Chaves in 882 AD. Note here once again the variety of planimetry of early Medieval castles, this one with an oval design.
Perafita moat and bailey is a wooden fortress that was built on top of a human-made mound. It gave shelter to the nearby populations during the 9th and 10th centuries, in consequence of frequent Viking raids.
Eiró moat and bailey is an artificial mound surrounded by a moat, which dominated the valley of Bastos near the Douro River. According to archaeological research it consisted of a wooden fortification surrounded by a stone wall.