Turku castle is a national monument and one the most remarkable medieval castles in Finland. It's also one of the largest existing castles in Scandinavia. A history of Turku castle begins from the year 1280. The Swedish conquerors of Finland intended it originally as a military fortress.
During 15th and 16th centuries its defences were strengthened and living quarters were added. The castle served as a bastion and administrative centre in Finland. It was also a residence for kings of Sweden, when they visited in Finland. During the struggles for power of Sweden in 14th and 15th centuries Turku castle was several times under siege. Probably the longest one occured in 1364-65, when German lord Albrecht von Mecklenburg besieged it over eight months before Swedish troops surrounded.
The heyday of Turku Castle was in 1556-1563, when King John III of Sweden lived there. During this castle was enhanced to Renaissance fashioned living palace. John III married Polish princess Catherine Jagellon who also lived in Turku short period in 1562-1563. In 1614, when King Gustav II Adolf visited the castle, a tremendous fire destroyed the wooden structure of the main castle almost completely. After this the main castle was abandoned and used partly as a store, partly just stood empty. In the 19th century castle was used as a prison. The last accident beset the castle in the summer of 1941 soon after the Continuation War had begun when an incendiary bomb hit the main castle.
Today Turku castle is Finland's most visited museum, with attendance reaching 200,000 in some years. In addition, many of the larger rooms are used for municipal functions.
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.