The White Tower is a monument and museum on the waterfront of the city of Thessaloniki. The present tower replaced an old Byzantine fortification, known to have been mentioned around the 12th century, that the Ottoman Empire reconstructed to fortify the city's harbour sometime after Sultan Murad II captured Thessaloniki in 1430. The tower became a notorious prison and scene of mass executions during the period of Ottoman rule.
The White Tower was substantially remodeled and its exterior was whitewashed after Greece gained control of the city in 1912. It has been adopted as the symbol of the city.
The White Tower houses an exhibition dedicated to the city of Thessaloniki and its history throughout various periods, organized by the city's Museum of Byzantine Culture.
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.