Ducové is famous for an archaeological site on the Kostolec hill, where an important Great Moravian castle has been unearthed. The castle, including a small palace, a Christian rotunda church, and a graveyard of local nobles, served as the administrative center of the Váh river valley during the 9th century and the first half of the 10th century. It was founded after the nearby Nitrian castle in Pobedim was destroyed during unification of Great Moravia by Mojmír I.
Ducové castle was destroyed itself by Magyar invaders around 955. Some parts of the castle (such as its palisades) have been reconstructed by archaeologists. Excavations of older settlements from the Stone Age, Bronze Age and the Roman era indicate that Ducové benefited from its location on the Amber Road well before the Great Moravian era.
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.