Hornberg Castle was built in 1216 by the Nobles of Sulz as a satellite castle to their main castle, Sulz Castle. Hornberg Castle was constructed to additionally secure the connecting road through the Steinbachklinge between the imperial cities of Hall and Rothenburg. Shortly after, the Sulz family built Kirchberg Castle on the other side of the Jagst ford, which evolved into Kirchberg Castle and the town of Kirchberg. Together with Sulz Castle, it secured the ford crossing of the Jagst, an important long-distance route at the time. All three castles were Staufen imperial castles.
In the years following the construction of Hornberg Castle, the village of Hornberg developed, serving as a forecourt for the castle, which was solely built as a core castle.
Subsequently, the castle was owned by several proprietors, making it a joint-heritage castle. In 1339, Albrecht of Hohenlohe-Uffenheim acquired the castle and its lordship. In 1360, fortifications were constructed to secure the castle. From 1504, the Crailsheim family appeared as the sole owners and have remained so to this day. In 1525, the castle was partially destroyed in the Peasants' War. In the following decades, it was rebuilt and transformed into a Renaissance castle. In 1588, the zwinger was rebuilt and economic buildings were constructed. In 1599, the west wing was rebuilt. In 1647, the outer castle courtyard was transformed into an expansive castle garden.
In 1944/45, the castle suffered significant roof damage during World War II, which the owners were able to quickly repair after the war.
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.