Northburgh Castle, also known as Green Castle or Greencastle Castle, is a 13th/14th-century ruin in Greencastle, Ireland. Completed in 1305 by Richard Óg de Burgh, it controlled Lough Foyle and served expansion plans. Edward Bruce captured it in 1316, and it later became an O'Doherty stronghold. The castle features an oval enclosure with a twin-towered gatehouse and a later large tower. Influenced by Edward I, it symbolized a shift from pure military structures to administrative centers. Damaged by cannon fire, the castle is now managed by the Irish government and accessible from the town and shore.
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.