Pedraza Castle dates from the 13th century and it was rebuilt in the 15th century by García Herrera and again in the early 16th century by the Dukes of Frías.
Poligonal ground plan, double enclosure, with cues and square turrets, plus an artificial moat excavated in the rock. The castle uses part of the wall and preserves the remains of one front, with Romanesque elements.
The tower that serves as the tower of homage uses a different bonding that the rest of the castle. It used to be owned by the Herrera and the Velasco (Dukes of Frías) families. The sons of the king of France, Frans I, were kept hostage in this castle in the 16th century.
The Gravensteen is a castle in Ghent originating from the Middle Ages. The name means 'castle of the counts' in Dutch. Arnulf I (918–965), Count of Flanders, was the first to fortify this place, building a medieval bastion on this high sand dune, naturally protected by the river Leie and its marshy banks. This bastion consisted of a central wooden building and several surrounding buildings, also in wood.
In the early 11th century, the wooden building was replaced by a stone residence, consisting of three large halls that made up three storeys, connected by a stone stairwell. The monumental stone staircase, the light openings, the fireplaces built into the walls and the latrines were signs of considerable luxury and comfort in those days. There was probably also a tower.