Rheinstein castle was constructed around 1316-1317. It was important for its strategic location. By 1344, the castle was in decline. By the time of the Palatine War of Succession, the castle was very dilapidated. During the romantic period in the 19th century, Prince Frederick of Prussia (1794–1863) bought the castle and it was rebuilt.
In 1975 the opera singer Hermann Hecher bought the castle. It's due to him that Rheinstein Castle became again one of the centres of attraction in the Rhine Valley. Around the apartment tower from the 14th Century you find neo-Gothic sets, turrets, terraces and iron stairs. Inside are stained glass windows and mural painting as well as a Renaissance fire-place and stylish furniture.
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.