Heemstede castle was first built in 1280 by Dirk van Hoylede from the region of Vlaardingen. Built, burned and rebuilt over the centuries, it was last torn down in 1810, after years of neglect. The monumental gatekeeper's house 'Nederhuys', built in 1630 remains intact as well as the foundations from the Middle Ages. The most famous owner of the castle was Adriaan Pauw, who bought it in 1620. He played a role in the Treaty of Munster, and built the bridge Pons Pacis to commemorate the peace treaty.
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.