The first historical mention of Gavnø is in King Valdemar's census book from 1231 where a 'house on Gavnø' is mentioned. The house was apparently a castle built to defend Denmark's western coasts. In the 15th century, Queen Margaret I opened St Agnes' Priory there, catering for nuns from aristocratic families. The chapel can still be seen in the castle's southern wing although it has since been extended.
In 1737, Count Otto Thott acquired Gavnø. He renovated and substantially extended the castle, creating today's three-winged, yellow-facaded building in the Rococo style where he was able to house his large collections of paintings, manuscripts and books. At his death, his library collection contained over 120,000 volumes, exceeding that of the Danish National Library. The park surrounding the castle is known for its rare trees, rose garden and, above all, its extensive display of bulbs.
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.