Cherven was one of the Second Bulgarian Empire's primary military, administrative, economic and cultural centres between the 12th and the 14th century. The town was a successor to an earlier Byzantine fortress of the 6th century, but the area has been inhabited since the arrival of the Thracians. Cherven was first mentioned in the 11th century in an Old Bulgarian apocryphal chronicle. It gained importance after 1235, when it became the seat of the medieval Bulgarian Orthodox Bishopric of Cherven.
During the second half of the 14th century, the stronghold's area exceeded 1 square kilometre and had intensive urban development, including a fortified inner city on vast rock ground in one of the Cherni Lom river's bends, and an outer city at the foot of the rocks and on the neighbouring hills. The town had a complex fortification system and was completely built up. Cherven grew to become a centre of craftsmanship in the 14th century, with iron extraction, ironworking, goldsmithing, construction and arts being well developed. The town was an important junction of roads from the Danube to the country's interior, which also made the town a key centre of trade.
Cherven was conquered by the Ottoman Turks in 1388 during the Bulgarian-Ottoman Wars, initially retaining its administrative functions but later declining in importance.
A large feudal palace with fortified walls reaching up to 3 metres wide, two well-preserved underground water supply passages, 13 churches, administrative and residential buildings, workshops and streets have been excavated. The three-storey tower, 12 metres high, from the 14th century has also been fully preserved and was even used as a model for the reconstruction of Baldwin's Tower in Tsarevets, Veliko Tarnovo, in 1930. The site has been a national archaeological reserve since 1965 and is a popular tourist attraction.
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.