The oldest parts of the Summersberg castle is the round 'Witch Tower' dating from the 14th century. Extensions and additions were made between 15th and 18th centuries. From 1619 to 1828 Summersberg was owned by Counts of Wolkenstein. In 1880 Ignaz Vinzenz Zingerle bought the castle. The descendants of Zingerle still own the castle.
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.