The Cathedral Basilica of the Holy Cross (Bazylika Katedralna Podwyższenia Krzyża Świętego) was built in the 15th century on the site where before there was a structure of the 11th and 13th centuries. It was rebuilt several times. With towers with a height of 73 meters is the tallest structure in the city. In the temple there is a painting of the Virgin of Opole, brought there permanently in 1702.
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.