Château or Donjon de Bours was most likely built in the 12th century by Hugues de Bours. Originally it would have had a bailey defended by a crenellated wall guarding several outbuildings. Both the bailey and the castle would have been moated. At present all traces of the bailey are gone.
Bours Castle is a keep built out of sandstone and has a rectangular plan with six corbelled turrets. It has walls of 70 cm thick and 2 floors. It is generally assumed that during the mid-13th century the keep would have been higher.
During the first half of the 15th century the castle was owned by Maillotins de Bours who restored and enlarged the castle but probably did not change the keep.
In 1543 Bours Castle was burned down.
At the beginning of the 20th century there was talk of demolishing the keep but luckily that did not happen. During the second half of the 20th century the keep was restored several times and used as a town hall.
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.