The bastion is a Renaissance-style fortification and surviving part of the Vilnius Defensive Wall. It consists of a tower merged in the city defence wall, underground gun ports and a connecting corridor, which turns into a 48-metre long tunnel. The bastion was built in the first half of the 17th century by the German military engineer Friedrich Getkant. The Bastion was severely damaged during the wars with Moscow in the middle of the 17th century. During World Wars I and II, German military arsenals were located in the building. You can enjoy a picturesque view of the Old Town from the Bastion terrace.
In 2007 the renovation works of the Bastion of Vilnius Defensive Wall were commenced. The Bastion has been closed for visitors since 2008.
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.