The town of Buitrago del Lozoya is completely surrounded by an ancient wall originally built by the Moorish people. Within these walls lies the ruins of the Buitrago de Lozoya castle. The style of the castle is a unique mix of Mudéjar (moorish) and Gothic designs – tall, solid square towers combined with the typical pentagonal shaped often used by the ancient Arabs. It was built in the 15th century. It has a rectangular plan, with seven towers of various shapes (round, pentagonal, square), all in stone. The interior is in ruins.
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.