Drysllwyn Castle stands on high ground overlooking the Tywi Valley with extensive views. It was built in about the 1220s by one of the princes of the kingdom of Deheubarth, and changed hands several times in the struggles between the Welsh and English over the ensuing centuries. It is considered one of the most important remaining structures built by a Welsh chieftain.
Drysllwyn was seized by Owain Glyndŵr in the summer of 1403 and when the English forces recaptured it they decommissioned it by blocking various access routes, walling up the gatehouse, removing the treads from stone stairs and even removing the hinges from the main gate. At some later stage, all the major buildings were burned to the ground. Following this a lot of the stone was removed from the site
The polygonal Inner Ward contains principal remains to the south west, with traces of the Middle and Outer Ward to the north east. The early thirteenth century curtain wall to the Inner Ward only stands 1m high. There is a garderobe to the east side, and a remodelled thirteenth century Gatehouse to the north east, surviving at foundation level only. On the south side of the Gatehouse is the Round Tower, the original keep. The foundations of the original Great Hall and Rhys ap Maredudd's hall survive.
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.