The Certosa di San Martino is a former monastery complex and now a museum. Along with Castel Sant'Elmo that stands beside it, this is the most visible landmark of the city, perched atop the Vomero hill that commands the gulf. A Carthusian monastery, it was finished and inaugurated under the rule of Queen Joan I in 1368. It was dedicated to St. Martin of Tours. During the first half of the 16th century it was expanded. Later, in 1623, it was further expanded and became, under the direction of architect Cosimo Fanzago, essentially the structure one sees today.
In the early 19th century, under French rule the monastery was closed and was abandoned by the religious order. Today, the buildings house a museum with a display of Spanish and Bourbon era artifacts, as well as displays of the presepe—Nativity scene—considered to be among the finest in the world.
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.