The keep of Crupet Castle was built in the 13th century and originally consisted of a square tower surrounded by a moat. The entrance was probably protected by a drawbridge and portcullis. In the 16th century, the keep was converted to a manor house. A corner tower was added, the windows were enlarged, and the timber top floor and roof were built. The drawbridge was probably also replaced at this time. The keep is not open for visits, but is highly visible from the surrounding roads.
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.