Church of San Andrés is an impressive church built in stone in the 16th century. In the same building, several architectural styles are to be seen, from the gothic to the neoclassical and the renaissance. The most Gothic parts are the nearest to the towers. It's the only remaining part of the Gothic building over which the current building was erected. Picturesque columns and archs. In the other part of the church we can see the sacristy, in neoclassical style. In the middle part we can see the stylistic evolution in the building. In the 'crucero' part we can see a Renaissance style. The church has also a baroque and renaissance-style altarpiece. The 18th-century organ, of classical style, is still in use and used for concerts.
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.