The Château de Roquessels was built in the 10th century. It was a dependency of the convent of Cassans, which collected tithes from the baron of Margon. In 1247, the inhabitants of the village, like all subjects of the Trencavels, viscount of Béziers, were released from their pledge of allegiance and submitted to the King of France. The castle resisted valiantly the assaults of Simon de Montfort's army. Today, the only remains are a chapel with fine windows and massive walls on three sides.
The castle was abandoned for more comfortable dwellings in the 18th century, in line with the changing tastes of the aristocracy of the period. The keep was destroyed during the French Revolution and its stones used to build the new mairie (town hall).
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.