The Porvoo Cathedral was originally made of wood. The first stone walls were built between 1410 and 1420 and in 1450 the church was expanded four meters towards east and six meters towards south.
The cathedral has been destroyed by fire numerous times; in 1508 by Danish and in 1571, 1590, and 1708 by Russian forces. On May 29, 2006, the outer roof collapsed after arson, however with the inner ceiling undamaged and the cathedral interiors intact. The Cathedral was reopened on 2 July 2008.
Porvoo Cathedral is situated in the middle of Porvoo well-preserved and beautiful old town, which is popular tourist attraction particurarly in summer season.
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.