Monasterio de San Juan was founded in 1091, when the kings Alfonso VI and Constance of Burgundy donated a small land to monk Lesmes, who came from the Chaise-Dieu abbey. In 1537 a fire destroyed practically the whole monastery. The reconstruction lasted until the confiscation. During the first half of the 19th century, several confiscations destroyed the heritage of the monastery and the hospital of San Juan. The monks were expelled from the monastery. The buildings were used as a prison.
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.