The Château des Quat'Sos name is of Gascon origin, describing the identical appearance of the four corner towers, the 'Four Sisters'. The castle is located on the promontory overlooking the confluence of the Garonne and the tributary Charros.
In 1224, permission was granted by King Louis VIII of France to build a castle. The castle was completed by King Henry III of England, while Duke of Aquitaine, to defend the English Duchy of Gascony. During the Hundred Years' War, the castle was fiercely disputed between English and French.
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.