The Abbey of La Clarté-Dieu was a Cistercian monastery. The abbey was founded in 1239 by the executors of Peter des Roches, Bishop of Winchester, as one of a pair, the other being Netley Abbey in Hampshire, England. The bishop had conceived the idea of founding a pair of monasteries some years before and had begun collecting the necessary endowments for them, but his death in 1238 prevented him from completing the project. The first monks arrived at the site in 1240.
The abbey was severely damaged in the course of the Hundred Years War and the cost of rebuilding proved a heavy burden on the finances of the community. Nevertheless, La Clarté-Dieu managed to survive until the French Revolution when it was closed and sold off along with all the other monasteries of France. Following the revolution the abbey was for a long time used as a farm and some of the buildings were allowed to fall to ruin. Despite this, much of the mediaeval abbey remains in excellent condition along with some fine post-mediaeval additions. The abbey is preserved as an historic monument and is open to the public.
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.