Le Perthus became French territory after the Treaty of the Pyrenees (1659). The Spanish captured Bellegarde in 1674 and began work on new fortifications in 1675. These were not very far advanced when the place was recaptured by the French. In 1678 Vauban designed for Bellegarde a strong pentagonal fort with a detached hornwork extending southwards towards the frontier.
The defences consist of a five bastioned trace, with an upper tier and a lower tier. In front of the more vulnerable sections of wall, there is a ditch. There are three demi-lunes, again only on the more approachable sides of the fortress - on the east there is a sheer precipice.
During the War of the Pyrenees, the fortress was besieged in May - June 1793 by the Spanish and then by the French (in 1794).
During World War II, the fort was used as a holding prison by the Gestapo for escaped prisoners of war and enemy agents.
The fort is open to the public between June and September only and includes exhibits on the history of the fort, its archaeology and the surrounding area.
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.