Possibly built on the foundations of a Roman castrum fortress, the Moosham castle was first documented in a 1191 deed. It was seized by the Prince-Archbishops of Salzburg about 1285 and from the 14th century onwards served as the residence of an episcopal burgrave. Under the rule of Prince-Archbishop Leonhard von Keutschach from 1495, the castle was rebuilt and extended. In 1520 it became an administrative seat of the Lungau region and was besieged during the German Peasants' War of 1524–25. Archbishop Wolf Dietrich Raitenau stayed here on his flight from Salzburg in October 1611, shortly before he was captured.
Archbishop Count Hieronymus von Colloredo dissolved the Moosham bailiwick in 1790, whereafter the castle decayed. In 1886 the Austrian explorer and patron of the arts Count Johann Nepomuk Wilczek purchased the ruin and had it restored. Up to today the complex is a private property, though its rooms featuring Wilczek's extensive art collection are accessible to the public.
References:The Gravensteen is a castle in Ghent originating from the Middle Ages. The name means 'castle of the counts' in Dutch. Arnulf I (918–965), Count of Flanders, was the first to fortify this place, building a medieval bastion on this high sand dune, naturally protected by the river Leie and its marshy banks. This bastion consisted of a central wooden building and several surrounding buildings, also in wood.
In the early 11th century, the wooden building was replaced by a stone residence, consisting of three large halls that made up three storeys, connected by a stone stairwell. The monumental stone staircase, the light openings, the fireplaces built into the walls and the latrines were signs of considerable luxury and comfort in those days. There was probably also a tower.