According to tradition, the Benedictine abbey of Herrenchiemsee was established about 765 by Duke Tassilo III of Bavaria at the northern tip of the Herreninsel. New findings however indicate an even earlier foundation around 620-629 by the missionary Saint Eustace of Luxeuil.
In 969 Emperor Otto I consigned the abbey to the Archbishops of Salzburg, who in about 1130 re-established Herrenchiemsee as a monastery of Canons Regular living under the Augustinian rule. In 1215, with the approval of Pope Innocent III, Prince-Bishop Eberhard von Regensburg made the monastery church the cathedral of a diocese in its own right, the Bishopric of Chiemsee, including several parishes on the mainland and in Tyrol.
In the course of the German Mediatisation, Herrenchiemsee Abbey was secularised in 1803 and the Chiemsee bishopric finally dissolved in 1808. The island was then sold; various owners demolished the cathedral and turned the abbey into a brewery. Plans for the complete deforestation of the island were blocked by King Ludwig II, who acquired Herrenchiemsee in 1873. He had the leftover buildings converted for his private use, the complex that later became known as the 'Old Palace', where he stayed surveying the construction of the New Herrenchiemsee Palace.
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.