The City wall of Visby (Swedish: Visby ringmur) is an old medieval defensive wall surrounding the city. The building of ringwall was probably started in the 13th century. Around 1280 it was rebuilt to reach its current height, along with the addition of its characteristic towers (although some towers were not constructed until the 15th century) It is part of the UNESCO World Heritage Site in Visby. The war in 1288 between the citizens of Visby and the Danish army gave the citizens of Visby a reason to continue the work with the wall. All together the city wall became 3.4 km, and it was finished in the beginning of the 14th century. At the time, the wall contained 29 towers, 27 of which are remaining today.
During the 1361 Battle of Visby, the main battle was fought within 300 meters of the North Gate of Visby (shown on the right). The peasant forces were ultimately unsuccessful, however, resulting in the citizens of Visby surrendering to the Danish forces.
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.