St. George's Basilica is the oldest surviving church building within Prague Castle. The basilica was founded by Vratislaus I of Bohemia in 920. It is dedicated to Saint George.
The basilica was substantially enlarged in 973 with the addition of the Benedictine St. George's Abbey. It was rebuilt following a major fire in 1142. The Baroque façade dates from the late 17th century. A Gothic style chapel dedicated to Ludmila of Bohemia holds the tomb of the saint. The shrines of Vratislav and Boleslaus II of Bohemia are also in the basilica. The abbess of this community had the right to crown the Bohemian queens consort.
The building now houses the 19th century Bohemian Art Collection of National Gallery in Prague. It also serves as a concert hall.
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.