Saarburg Castle was one of the first and most impressive castles (Höhenburgen) in the West, built by Graf Siegfried von Luxemburg in 964. It was damaged in 1431 by troops of Ulrich von Manderscheid. Johann II von Baden rebuilt the castle later. It was conquered several times in the wars of 17th-early 18th century and finally left to decay in 1734.
The castle hill is surrounded by high fortified walls. With a depth of 60 metres, the fortress well almost reached down to the river bed of the Saar. The upper part of the tower, which offers a wonderful view of the Saar valley and the pilgrimage church of St. Mary in the Beurig district.
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.