The Crusader structures called the Knights' Halls or the Citadel of Acre originally served as the Knights Hospitaller Compound. They extend over an area of c. 8,300 square meters. Archeological remains from the Hellenistic Period (300-63 BC), from the Early Arab Period (638-1099 CE), to a large extent from the Crusader Period (1291-1104 CE) and primarily from the 13th century, were uncovered in the compound area.
It was in the 13th century that Acre was the capital of the Crusader Kingdom of Jerusalem. The destruction of the Crusader structures during the Mamluk Period (1291-1517) left its mark on the compound.
During the Late Ottoman Period (1750-1918 CE), the citadel was built as part of the city's defensive formation on the ruins of the Crusader fortress and during the British Mandate (1918-1948), activists of Jewish Zionist resistance movements were held prisoner there and it served as the main prison in the North of Israel. The archaeological excavation of the Crusader remains and the exposure of a multi-period complex depict Acre's two golden ages – the thirteenth century and the eighteenth & nineteenth centuries.
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.