Taggenbrunn Castle site was already used as a Celtic-Roman hillfort settlement in the 6th century BC. The first mention of current castle dates from 1142. The castle was destroyed in 1258 in a rebellion agains Duke Albrecht I and rebuilt ten years later. Later the castle was owned by the Holy Roman Empire and archbishopric of Salzburg. The castle was expanded in 1497-1503. In the 17th and 18th centuries Taggenbrunn was left to decay. Today there is a wineyard and restaurant.
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.