Minat al-Qal'a ('harbour of the fort') is a medieval coastal fort protecting the port known as Ashdod. The fort was built by the Umayyads and later restored by the Crusaders.
The fort was built by the Umayyad Caliph Abd al-Malik ibn Marwan (reign 685–705 CE) before the end of the 7th century on top of Byzantine-era remains. It was in use during the 10th-11th centuries, and was restored and used again by the Crusaders in the late 12th century after sustaining serious damage from the 1033 earthquake. The fort was meant to protect the port from raids by the Byzantine navy, while the port itself was used by the same navy to exchange Muslim prisoners for ransom.
Archaeological excavations show that the fort was restored and reused during the Crusader period. They come to prove what was already known from documents from the era, which indicate that Nicolas de Beroard, a knight of lord Hugh of Ramla, was in charge of the stronghold in 1169. From this period it is known as Castellum Beroart.
The port stops being mentioned during the Ayyubid and Mamluk periods, making it likely that it was destroyed by the Muslims along with the other port cities from the coast of Palestine, due to fears that they might again be used by Crusader invasions from the sea.
The almost rectangular fortress (35x55 meters) was enclosed by a six to seven meters high curtain wall. It has four solid corner towers, and two semicircular ones flanking each of the two huge gates that gave access to the stronghold from the west and east.
References: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.