The Château de Gisors was a key fortress of the Dukes of Normandy in the 11th and 12th centuries. It was intended to defend the Anglo-Norman Vexin territory from the pretensions of the King of France. King William II of England ordered Robert of Bellême to build the first castle at Gisors. The first building work is dated to about 1095, and consisted of a motte, which was enclosed in a spacious courtyard or bailey. Henry I of England, Duke of Normandy, added an octagonal stone keep to the motte.
In 1193 the castle fell into the hands of the King of France and thereafter lost temporarily its importance as a frontier castle. A second keep, cylindrical in shape, called the Prisoner's Tower, was added to the outer wall of the castle at the start of the 13th century, following the French conquest of Normandy. Further reinforcement was added during the Hundred Years' War. In the 16th century, earthen ramparts were built. Since 1862, Château de Gisors has been recognised as a monument historique by the French Ministry of Culture.
Château de Gisors is also known for its links with the Templars. Put into their charge by the French king between 1158 and 1160, it became the final prison of the Grand Master of the Order, Jacques de Molay, in 1314.
References:Sigmaringen Castle was first mentioned in the year 1077 in the chronicles of Petershausen monastery. The oldest parts of the castle are concealed beneath the alterations made during the 17th and the 19th centuries. The secret of the earliest settlement built on this defendable rock will never be fully revealed: large-scale excavation work would be necessary, which the extensive land development renders impossible. Judging from the many Roman remains unearthed in the area around Sigmaringen, the 12th century keep known as the 'Roman Tower' could be traced back to a Roman predecessor.
The castle remains that have been preserved (gate, great hall and keep) date back to the Staufer period around 1200. The castle remains were integrated into subsequent buildings. The foundations of the castle buildings are to a large extent identical to the surrounding castle wall.
These remains give us a good idea of how the castle might have looked during the 12th century.