Viby was first mentioned in 1331. The current castle was built by Charles IX of Sweden to his wife Kristina between 1622-1626. The Dutch Renaissance style castle was designed by Casper van Panten. After the Crown donated Vibyholm to Gustaf Gustafsson af Vasaborg it has been owned by several families. The castle was left to decay in the early 1700s, but restored by Gustaf Ulf Claesson Bonde af Säfstaholm in the 1730s. The next restorations were made in the early 1800s and between 1852-1854. Today Vibyholm is privately owned and not open to the public.
References:Duino Castle was built by the Wallsee family in 1389 on the cliffs overlooking the Gulf of Trieste. It replaced an older castle from the 11th century. Over time, the Wallsee family disappeared and the castle, after having been used as a prison, became the residence of the Luogar and Hofer.
At the end of the 19th century it became the property of Prince Alexander von Thurn und Taxis from the Czech branch of the House of Thurn and Taxis. It remains with the family to this day with his great-grandson Prince Carlo Alessandro della Torre e Tasso, Duke of Castel Duino the current owner. The castle has been opened to the public as a museum and park.