Château de Kaysersberg was built for Albin Woelflin, imperial bailiff for Frederick II, Holy Roman Emperor, around 1220. The site was acquired in 1227 by the lords of Horbourg and Ribeaupierre. It had an important strategic role as it allowed the Empire to close off one of the routes across the Vosges Mountains towards Lorraine.
The circular keep is the oldest part of the castle and one of the first of this type in the upper Rhine valley. It was designed at the same time as the keep at the Château de Pflixbourg. The first curtain wall, which included the keep, was replaced after 1261 by a wall enclosing the keep, according to a contemporary plan, which allowed an uninterrupted circuit of the walls and strengthened defences on the side likely to be attacked. In the 14th century, the castle was the residence of the imperial provost or bailiff. Following a fire, the enceinte was raised to 4 m.
In the second half of the 15th century, the castle defences were modernised in response to developments in artillery and firearms; the crenels were closed with wooden shutters, the merlons were equipped with firing slits and the round walk was completely covered. In this period, the castle was merely a sub-bailliage and personnel were heavily reduced. During the German Peasants' War (1524-1525), the castle was besieged. It was restored by Lazarre de Schwendi in 1583.
According to archaeological excavations and studies, the castle was abandoned at the end of the 16th century. After the French Revolution, it was declared a national asset and sold to François Joseph Boecklin de Boecklinsau, who planted vines, and later passed to the Bastard family.
The castle is largely built from granite. It stands at an altitude of 295 m and dominates from 50m the north side of the town. The castle has a triangular plan dominated by the circular keep in the highest point. The keep is 11 m in diameter with walls 4.42 m thick. The original parapet has been kept to a height of 0.55 m, with the crenels and merlons restored. The spiral staircase is concrete. Access is to the first floor, through an arched doorway.
The spacious third floor served as a storeroom and provided access to the platform which was originally covered. The keep had a purely military function. The main residential buildings were situated against the east curtain wall. On the other side, towards the town, was a large lower courtyard. The entrance to the castle, in the east, was by an arched doorway with a barbican; to the left is a cruciform cannon opening and a circular firing hole. The castle's enceinte is linked to the town's by curtain walls with a round walk.
References:Inverness Castle sits on a cliff overlooking the River Ness. The red sandstone structure evident today was built in 1836 by architect William Burn. It is built on the site of an 11th-century (c. 1057) defensive structure. Today, it houses Inverness Sheriff Court.
The castle is said to have been built by Máel Coluim III of Scotland, after he had razed to the ground the castle in which Macbeth of Scotland according to much later tradition, murdered Máel Coluim"s father Donnchad I of Scotland, and which stood on a hill around 1 km to the north-east.
The first Inverness Castle was partially destroyed by King Robert I of Scotland and a replacement castle was sacked in the 15th century by the Clan Donald during the Siege of Inverness (1429). The castle was occupied during the Raid on Ross in 1491.
In 1548 another castle with tower was completed by George Gordon, 4th Earl of Huntly (1514–1562). He was constable of the castle until 1562.