The Château de Dourdan was built at the request of Philip Augustus in the 1220s in the place of a wood structure. The castle became the property of Jean de Berry in 1385. It was besieged during the French Wars of Religion. Among some of the notable personages who resided in the castle were Philip IV of France's daughter-in-law, Joan II, Countess of Burgundy, detained there from 1314 to 1315 in relation to the Tour de Nesle affair, and La Hire, one of Joan of Arc's comrades-in-arms.
At the end of the 17th century, the Château de Dourdan was given to the Duke of Orléans who turned it into prison. The donjon was used as a prison until 1852. It now houses a museum of local history.
The fortification is characteristic of the military architecture of this period. It is built on a square pattern, with towers at three of the corners and an isolated donjon at the fourth. The walls are punctuated by towers in the middle of each side, and two, on the east side, flank the gatehouse. A deep stone-lined dry moat follows the outline of the castle.
The donjon, the major defensive component of the castle, measures approximately 30 metres in height and 13.6 metres in diameter. It is the typical of the donjons being built by King Philip II Augustus of France at this time, like at Rouen and other French nobility throughout the 13th century.
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.