The Palace of Omurtag is an archaeological site in northeastern Bulgaria dating to Late Antiquity and the Early Middle Ages located near the village of Han Krum in Shumen Province. The site has been pinpointed as the location of a fort and palace of Omurtag, ruler (kanasybigi) of the First Bulgarian Empire in 815–831, as mentioned in the Chatalar Inscription of 822. Earlier structures in the vicinity of the fortress have been identified as the Arian episcopal see of a Gothic bishop.
The main feature of the archaeological site is the early-9th-century Bulgarian fortified rampart with Omurtag's palace within its limits.
The earliest ruins at the Palace of Omurtag site include four churches, two of which built on top of each other; a bath; and fortified walls, all dating to Late Antiquity (roughly 250–650 CE). Three of the churches and the bath lie outside the medieval fortification, while one of the churches and the traces of ancient walls have been excavated within its limits.
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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.