Capilla Castle was built by Moors to the site of ancient Roman fortifications. It was conquered by Christian king Ferdinand III of Castile and León in 1226 and rebuilt soon after. It stands on a crag where it reveals its structure in the shape of an irregular polygon attempting to adapt to the abrupt terrain. A barbican defends the main door, which leads onto the two courtyards. Inside, the cylindrical towers, the half-demolished allure and the remains of a machicolation give you an idea of the defensive nature this castle had.
In spite of its current appearance, you can still see the ruins of the old Arabic walls, both on the south side and the north, and the original stone paving of the staircases and rooms.
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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.