Aiello Calabro Castle was probably buillt in the Byzantine period in the 9th century against Arabian raids. It was besieged four months by Norman count Robert Guiscard in 1065. He lost two of his nephews in the siege.
The current ruins date mainly from the 15th century. In the 16th century it was one of the most powerful castles in southern Italy. Aiello Calabro castle was destroyed by earthquakes of 1638, 1783 and 1905. Today part of curtain walls and towers remain.
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.