Schönbühel castle origins date from the early 12th century. The castle is built on rock approximately 40 metres above the level of the river Danube. A Roman fortress may have stood there before. The castle was begun in the early 12th century by Marchwardus de Schoenbuchele as a defensive fortress. When his descendant Ulrich von Schonpihel died at the beginning of the 14th century, the family was extinguished. The castle was briefly owned by Conrad von Eisenbeutel, and then by the Abbey of Melk. In 1396 it was sold to the brothers Caspar and Gundaker von Starhemberg. It remained in the Starhemberg family for more than 400 years, but fell into disrepair.
In 1819 Ludwig Josef Gregor von Starhemberk sold it, together with the castle of Aggstein, to Count Franz von Beroldingen, who had it renovated and partially rebuilt, so that by 1821 it was again habitable.
In 1930 the Schönbühel estate was sold to Count Oswald von Seilern und Aspang.References:
Goryōkaku (五稜郭) (literally, 'five-point fort') is a star fort in the Japanese city of Hakodate on the island of Hokkaido. The fortress was completed in 1866. It was the main fortress of the short-lived Republic of Ezo.
Goryōkaku was designed in 1855 by Takeda Ayasaburō and Jules Brunet. Their plans was based on the work of the French architect Vauban. The fortress was completed in 1866, two years before the collapse of the Tokugawa Shogunate. It is shaped like a five-pointed star. This allowed for greater numbers of gun emplacements on its walls than a traditional Japanese fortress, and reduced the number of blind spots where a cannon could not fire.
The fort was built by the Tokugawa shogunate to protect the Tsugaru Strait against a possible invasion by the Meiji government.
Goryōkaku is famous as the site of the last battle of the Boshin War.