St Catherine's Castle is a Henrician castle in Cornwall, England, built by Thomas Treffry between approximately 1538 and 1540, in response to fears of an invasion of England by France and the Holy Roman Empire. The D-shaped, stone fortification, equipped with five gun-ports for cannon, overlooked the mouth of the River Fowey in Cornwall. It was protected by a curtain wall and the surrounding cliffs.
The castle remained in use for many years until it was closed at the end of the Napoleonic Wars in 1815. Brought back into service in 1855 during the Crimean War, it was fitted with two new artillery positions, but it soon became obsolete and was abandoned. During the Second World War the castle was refortified and used to house a battery of naval guns, protecting the coast against the threat of German attack. At the end of the conflict the castle was restored to its previous condition and is now managed by English Heritage as a tourist attraction.
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.