The original Château de Coustaussa was built by the Trencavels, Viscounts of the Razès, in the 12th century. It was the stronghold of Cathars until Simon de Montfort and his Crusaders conquered it during the Albigensian Crusade. After the Crusades, the Castle came into the possession of the de Montesquieu family. The present Château was apparently still in good shape until the 19th century, when an enterprising local realised that he could turn a few Francs by stripping out and selling the woodwork.
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.