The amphitheatre of Catania is the most complicated and largest of all the amphitheatres in Sicily. It was built in the Roman Imperial period, probably in the 2nd century AD, on the northern edge of the ancient city at the base of the Montevergine hill. Only a small section of the structure is now visible, below ground level, to the north of Piazza Stesicoro.
The external diameter was 125 x 105 metres, while the external circumference was 309 metres. From the theatre's dimensions it can be calculated to have held 15,000 spectators and almost double that number with the addition of wooden bleachers for standing spectators. According to an uncertain and unconfirmed tradition, it was intended that naumachiae (staged sea battles) take place in the amphitheatre, using the ancient aqueduct to fill the arena with water.
According to Cassiodorus, in the 5th century, Theodoric, King of the Ostrogoths, allowed the inhabitants of the city to spoliate the theatre for building material for the construction of stone buildings.
In the 13th century, according to tradition, the amphitheatre's vomitoria (entranceways) were used by the Angevins to enter the city during the Sicilian Vespers. In the following century, the entrances were walled up and the ruins were incorporated into the Aragonese fortifications (1302).
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.