Alburquerque was conquered from Moors by Ferdinand II of León in 1166. It changed hands couple of times before was finally in the hands of Christians in 1217. The castle was built in the late 13th century.
In the mid-15th century Álvaro de Luna, Master of the Order of St. James, built the famous keep. But that is not the only identifying mark on this castle as it has several palace-style out buildings, some outer defence resources in the barbican and a curious pentagonal tower, crowned battlements with sharp points ending in balls. Furthermore, the fortress is protected by three levels of walls scattered with small towers and several doors.
In the early 18th century the city was in the hands of Portuguese and several Vauban-style bastions were added to the complex.
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.