The Walls of Thessaloniki are the city walls surrounding the city during the Middle Ages and until the late 19th century. Large parts of the walls, including the entire seaward section, were demolished as part of the Ottoman authorities' restructuring of Thessaloniki's urban fabric. The city was fortified from its establishment in the late 4th century BC, but the present walls date from the early Byzantine period, ca. 390, and incorporate parts of an earlier, late 3rd-century wall. The walls consist of the typical late Roman mixed construction of ashlar masonry alternating with bands of brick. The northern part of the walls adjoins the acropolis of the city, which formed a separate fortified enceinte, and within it lies another citadel, the Heptapyrgion (Seven Towers), popularly known by the Ottoman translation of the name, Yedi Kule.
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.