Donegal Castle was the stronghold of the O'Donnell clan, Lords of Tír Conaill and one of the most powerful Gaelic families in Ireland from the 5th to the 16th centuries. For most of the last two centuries, the majority of the buildings lay in ruins but the castle was almost fully restored in the early 1990s. It is now open to the public.
The castle consists of a 15th-century rectangular keep with a later Jacobean style wing. There is a small gatehouse at its entrance mirroring the design of the keep. The complex is sited on a bend in the River Eske, near the mouth of Donegal Bay, and is surrounded by a 17th-century boundary wall. Most of the stonework was constructed from locally sourced limestone with some sandstone.
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.