The Angevine-Aragonese castle of Gallipoli dates back to the 13th-14th centuries, but the town used to have a stronghold already during Roman time, together with towers enlarged by the Byzantines and by the Normans. The Angevins and the Aragonese modified the structure of the fortress, but Francesco di Giorgio Martini was the one who made important changes. During the 19th century the moat was filled up and the arches which used to support the lift bridge were filled in.
The fortress has a square base strengthened by the four towers. The tower Vedetta, topped by merlons, has a polygonal shape. The other towers are surrounded by a string course and are decorated with small arches. The eastern curtain, the Rivellino, is a fifth circular tower separated from the rest of the walls and has not been renovated yet. Inside it, there are large rooms with barrel and cross vaults.
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.