Hay Castle is a medieval fortification and 17th-century mansion house in the small town of Hay-on-Wye, Wales. Originally constructed as part of the Norman invasion of Wales, the castle was designed as a ringwork overlooking the town in either the late-11th or early-12th centuries. It was rebuilt in stone around 1200 by the de Braose family and then had a turbulent history, being attacked and burnt several times during the First and Second Barons' Wars, the wars with the Welsh princes, the rebellion of Owain Glyndŵr and the Wars of the Roses.
In the 17th century a Jacobean mansion house was built alongside the medieval keep and the property became a private home. Serious fires in 1939 and 1977 gutted the castle and, despite repairs in the 1980s, by the 21st century much of the building was derelict and unstable. Since 2011 it has been owned by the Hay Castle Trust who plan to renovate the property to form an arts and education centre.
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.