Built around 1250 by the lords of Berkule, Calenberg Castle was granted to the Papenheim family in 1307 and later became known as Rave von Calenberg. After a feud over inheritance in 1464, it was resolved in 1471. In 1868, Hugo Schuchard purchased the estate, including the castle, and extensively renovated it from 1880 to 1884. The castle served various purposes over the years, including housing refugees after 1945. In 1972, it was acquired by Karl-Heinz Rehkopf and faithfully restored.
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.