Wildenburg is a ruined castle near Kempfeld in the county of Birkenfeld. The ruins lie in the Hunsrück mountains between the Idar Forest to the north and the town of Idar-Oberstein.
The predecessor of the Wildenburg was probably a Celtic refuge fort with double ramparts from the La Tène period (ca. 450-50 B.C.). The Wildenburg rampart is one of a number of Celtic fortifications in southern Hunsrück between the hillfort of Otzenhausen, the Ringkopf, the Altburg and the Alteburg in Soonwaldsteig. A short section of the rampart has been reconstructed as a 'Gallic Wall' (murus gallicus).
Around the year 350 AD a late Roman fort was established on the Wildenburg for a short time.
In the Late Middle Ages Wildenburg was built by the Wildgrafen family on the rocks at the western tip of the circular rampart. It was first mentioned in 1330 and was pillaged and destroyed by marauding troops from Lorraine in 1651. After being partially rebuilt in 1660, the lower ward of the castle acted as the administrative headquarters for the Amt of Wildenburg until the abolition of the county in the 1792.
Of the upper bailey (Oberburg) that was built on rocks only a few wall remains have survived. However, in 1980, a 22-metre-high observation tower was built on the top of the rocks that was opened in 1981.
In 1859 the buildings of lower bailey (Unterburg), including the gate tower, domestic buildings and enceinte, were restored for the Prussian Forestry Commission. These buildings were further converted into the present-day castle cafe and headquarters of the Hunsrück Club.
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.