The Clementinum is huge complex of buildings and churches situated between Křížovnické Square, Charles Street and the bank of Vltava. It was established in the place of the former Dominican monastery, on the property that was given to the Jesuits at their arrival to Prague in 1556. The historic task of the Jesuits was the re – catholicisation of the Czech environment. The residential Jesuit headquarters in Prague originated primarily in the years 1653-1726 and it consists of four wings and four yards with the tower in the middle. The buildings in the complex are in early Baroque, late Baroque and Classical styles. The Jesuits established a college and a convent for nobles, they were running all types of schools that gradually gained prestige and became a concurrence to the Prague University. Their education was at a high level and many great Czech scholars studied here. Gradually, the Jesuit University merged with the Prague University and the Charles-Ferdinand University was established.
The best architects and artists contributed to the construction of the Clementinum, which includes the Italian architects, Francesco Caratti, Carlo Lurago, Domenico Orsi and also the Czech sculptor Jan Jiří Bendl. In the complex we can find thirteen sundials and astronomical and meteorological equipment, which are located in the astronomical tower of Clementinum. On the top of the dome stands a lead statue of Atlas, which was probably the work of Matthias Braun. Systematic meteorological and astronomical measurements and research were performed here since 1775, which is unique in the world. The Citizens of Prague also knew the correct time thanks to Clementinum. There are a hundred and seventy-two steps to the top of the tower but the view over Prague is worth it. In the complex there is a church of St. Salvador, church of St. Clement, Vlašská Chapel, which served the Italian community, and another chapel known as the Hall of Mirrors, which now hosts unique concerts.
After Josef II. cancelled the Jesuits order the public university library was established in Clementinum. At present, it houses the National Library of the Czech Republic, the largest and most important institutions of its kind; the fund has more than six million publications. The historical halls of the library can be seen even in an organized tour. The Baroque library-study room has beautiful frescoes that symbolize the temple of wisdom and it is considered to be the most beautiful room in Clementinum.