There have been settlements on the site of Châtel-Argent castle since prehistoric times and through the Roman Era. There is a chapel dedicated to Saint Columba of Sens which was built sometime between 1050 and 1070. The castle first appears in a document in 1176 as Castrum Argenteum. The castle was improved around 1275 under the direction of Count Peter II's architect James St. George and castle grew to the configuration we see today. This castle had always been owned by the counts and the dukes of Savoy.
The ruins can be accessed from Villaneuve by walking The Rampa, a staircase carved into the rock of the valley wall. The castle is located in the town of Villeneuve in the Aosta Valley region, at about 10 km west of the city of Aosta. The most prominent feature left in the ruins is its watchtower keep measuring just under 10 meters in diameter which overlooks the town below. The ruins themselves cover about 6,300 square meters. When the castle was whole, it was estimated to be able to hold 700 people in times of danger.
References:Rosenborg Palace was built in the period 1606-34 as Christian IV’s summerhouse just outside the ramparts of Copenhagen. Christian IV was very fond of the palace and often stayed at the castle when he resided in Copenhagen, and it was here that he died in 1648. After his death, the palace passed to his son King Frederik III, who together with his queen, Sophie Amalie, carried out several types of modernisation.
The last king who used the place as a residence was Frederik IV, and around 1720, Rosenborg was abandoned in favor of Frederiksborg Palace.Through the 1700s, considerable art treasures were collected at Rosenborg Castle, among other things items from the estates of deceased royalty and from Christiansborg after the fire there in 1794.
Soon the idea of a museum arose, and that was realised in 1833, which is The Royal Danish Collection’s official year of establishment.