The castle of Aymavilles is certainly the most characteristic and recognizable element of the Aymavilles for its position and architecture characterized by the four cylindrical towers crowned by 'murder holes' that enclose a central body with a square base.
The building, the origins of which date back to 12th century, was repeatedly reconfigured, changed its use from defensive to that of elegant lordly residence inside a great park.
The first record of the fiefdom and the castle date back to 1278, when it was simple a four-sided tower surrounded by a wall, according to the widespread type of the oldest Valdostan castles. Today, the large surrounding walls of the 13th century tower still exist, characterized by being strongly banked, along with a spinal wall divides it into sections at full height.
In 1357, Aimone de Challant became subject to fiefdom three years before the fiefdom of Aymavilles by Amedeo VI of Savoy, allowing it to operate as the defensive reinforcement of the facility, probably considered too vulnerable particularly the level approach on the surrounding land. The four corner towers were thus made: these have circular bases and are unequal in diameter, height and type of crenellations; 'murder holes' and arrow loops were also built, in addition to a double wall with a moat and draw bridge.
At the beginning of 18th century, the external fortifications were demolished and the land was arranged in terraces and gardens, changing the designated use of the building.
After many changes in ownership, the castle was purchased in 1970 by the Regional Administration, which has undertaken major restructuring in these past years.References:
Kristiansten Fortress was built to protect the city against attack from the east. Construction was finished in 1685. General Johan Caspar von Cicignon, who was chief inspector of kuks fortifications, was responsible for the new town plan of Trondheim after the great fire of 18 April 1681. He also made the plans for the construction of Kristiansten Fortress.
The fortress was built during the period from 1682 to 1684 and strengthened to a complete defence fortification in 1691 by building an advanced post Kristiandsands bastion in the east and in 1695 with the now vanished Møllenberg skanse by the river Nidelven. These fortifications were encircled by a continuous palisade and thereby connected to the fortified city. In 1750 the fortress was modernized with new bastions and casemates to protect against mortar artillery.