Schloss Heiligenberg is a Renaissance-style castle owned by the Fürstenberg family. It is located on a plateau 730 metres above sea level, with views down onto the Bodensee and the Alps. It was first built in the Middle Ages - in 1250 count Berthold of Heiligenberg built a burgh on the site, which was bought in 1277 by count Hugo of Werdenberg. Under the counts of Werdenberg-Heiligenberg, the castle expanded during the late Middle Ages.
Through countess Anna of Werdenberg's marriage to count Friedrich zu Fürstenberg in 1516, the burgh passed to the house of Fürstenberg in 1535 - it is still owned by that family today. Shortly before his death in 1559, Friedrich decided to remodel the castle in the Renaissance style. The building as it is seen today dates to count Joachim (1538–1598), who from 1560 to 1575 rebuilt the late medieval burgh into a 'schloss', with a Renaissance-style courtyard and an extended ballroom wing to the south.
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.