The Tomb of the Unknown Soldier is dedicated to the unknown soldiers who have given their lives for Poland. It is one of many such national tombs of unknowns that were erected after World War I, and the most important such monument in Poland.
The monument, located at Piłsudski Square, is the only surviving part of the Saxon Palace that occupied the spot until World War II. Since 2 November 1925 the tomb houses an unidentified body of a young soldier who fell during the Defence of Lwów. At a later date earth from numerous battlefields where Polish soldiers have fought was added to the urns housed in the surviving pillars of the Saxon Palace.
The Tomb is constantly lit by an eternal flame and assisted by a guard post by the Representative Battalion of the Polish Army. It is there that most official military commemorations take place in Poland and where foreign representatives lay wreaths when visiting Poland.
The changing of the guard takes place on the hour of every hour daily and this happens 365 days a year.
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.