The Church of St. Nicholas was first mentioned in 1220 and was expanded over time in the 14th century before taking its final shape in the year 1465. The architectural style is mainly Gothic.
The church consists of three naves. It has well-preserved stain glass windows, and a large rose window over a pointed arched portal, a number of wooden sculptures of saints and paintings that date from different periods. Of particular importance is the large altar and pulpit.
Outside is a tall clock tower with a sundial. Old tombstones line the walls and various paintings from the life of Jesus Christ.
Behind the church is St. Barbara's Chapel. The layout of the chapel is octagonal. It was built by the architect Hans von Burghausen in 1450, who also designed the Hospital Church. The basement served as the ossuary while the main floor was used for religious ceremonies and prayers. It features a number of wooden pews and a wooden Gothic altar, flanked by two altars from the Baroque period. Outside the entrance has a painting depicting Saint Christopher.
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.