The Teatro Romano in Trieste was built in the first century BC and expanded in the second century AD. It had seats for from 3,500 to 6,000 visitors. It was probably built by the Trieste Quinto Petronio Modesto , prosecutor Emperor Trajan.
Over the centuries, the theater was left under the houses that were built above. Considered lost, it was identified in 1814 and unearthed in 1938 during the demolition of this part of the old city. The statues and inscriptions found in the excavations are kept in the San Guisto Castle.
Nowadays Teatro Romano is still occasionally used for outdoor summer shows.
FYI this is not an amphitheater because it is not in the round. It is simply a theater.
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.