Hilgartsberg Castle lies on a mountain on the left bank of the Donau River. It was first mentioned in 1112. It was a fief of the Bishop of Bamberg and cared for by the Counts of Sulzbach. When the counts died out in 1188 the castle fell to a couple of sons of Frederick I, Holy Roman Emperor. They lent it out to Walchunus von Kamm.
In 1326 the castle came into the hands of the House of Eck. When Peter Ecker von Eck fell out of favor with Duke Albrecht I of Bavaria, the castle was besieged and conquered by the Duke in 1357. Albrecht then strengthened the castle and installed a castellan. Later it was lent out to several nobles. In 1617 it was used by the Fugger family, who considerably enlarged the castle after a big fire had damaged it in 1626.
In 1704, during the War of the Spanish Succession, Hilgartsberg Castle was occupied by Austrian troops. In 1742, during the War of the Austrian Succession, the Austrian troops returned and with help of Hungarian troops conquered and burned down the castle. After that it was a ruin and was never rebuilt.
Later the ruins were owned by a local brewer and the Bavarian State. And in the 1970s part of it served as the village school. At present Hilgartsberg Castle can freely be visited. It is used as a venue for cultural events.
References:The Clementinum is a historic complex of buildings in Prague. Until recently the complex hosted the National, University and Technical libraries, the City Library also being located nearby on Mariánské Náměstí. The Technical library and the Municipal library have moved to the Prague National Technical Library at Technická 6 since 2009. It is currently in use as the National Library of the Czech Republic.
Its history dates from the existence of a chapel dedicated to Saint Clement in the 11th century. A Dominican monastery was founded in the medieval period, which was transformed in 1556 to a Jesuit college. In 1622 the Jesuits transferred the library of Charles University to the Klementinum, and the college was merged with the University in 1654. The Jesuits remained until 1773, when the Klementinum was established as an observatory, library, and university by the Empress Maria Theresa of Austria.