The Cathedral Basilica of Saint Stephen was built in the late 1010s by Saint Stephen I, the first King of Hungary. It was the most significant place of the Kingdom of Hungary in the Middle Ages, as it contained the crown jewels, including the throne, the Holy Crown of Hungary, the treasury and the archives. 37 kings and 39 queens consort were crowned in this basilica and 15 were buried in it. In 1543, the Turks occupied Székesfehérvár. The royal graves were ransacked and the basilica was used to store gunpowder while St. Martin's Cathedral in Pozsony became the new coronation site.
In 1601, the valuable building was destroyed by fire. Just in 1601, the Ottoman rule of the city was interrupted for about one year. Illustrations of the 17th century suggest that the fire and probable blow up was caused by Christian artillery in the course of the Christian conquest.
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.