Close to the Catacombs of San Callisto are the large and impressive Catacombs of Domitilla (named after Saint Domitilla), spread over 15 kilometres of underground caves.
The Domitilla Catacombs are unique in that they are the oldest of Rome's underground burial networks, and the only ones to still contain bones. They are also the best preserved and one of the most extensive of all the catacombs. Included in their passages are a 2nd-century fresco of the Last Supper and other valuable artifacts. There are almost 150,000 bodies buried in the Catacombs of St. Domitilla.
They are the only catacombs that have a subterranean basilica; entrance to the catacombs is achieved through this sunken 4th-century church, at via delle Sette Chiese 282. In the past, the basilica had become unsafe, and was abandoned in the 9th century. It was rediscovered in 1593, and much of it was reconstructed in 1872.
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.