The earth and timber stronghold Gerdauen was constructed by the Teutonic Knights in 1270. After a subsequent Prussian uprising, the Knights were too weak to keep hold of all their fortresses. Gerdauen was burnt down, but once the Prussian uprising was put down, the Teutonic Knights returned here and began to raise new fortifications. By 1310, a new stronghold had been completed. At that time it was guarded by embankments, moats and shelters. Inside the ring of fortifications, stone and brick buildings for a convent of Teutonic brothers were constructed.
Initially the Knights planned that Gerdauen would become a seat of a commander, known as komtur. But this idea was soon relinquished because of the proximity to the Lithuanian lands and frequent attacks staged by Lithuanian troops. Gerdauen for example was attacked in 1336, 1337 and in 1366.
Although in 1406 Gerdauen Castle was surrounded by a ring of fortified walls less than half a century later, in 1455, which was during the Thirteen Years' War, the fortress was severely damaged. In 1670 it stood empty. Soon afterwards it was sold to a private owner. All that had remained of the original buildings were the cellars.
In 1872 a new beautiful palace was raised on this location. Gerdauen flourished until 1814, that is until the outbreak of World War One. In that year, the town was a witness and a victim of a bloody fight with the Russian army. Gerdauen was not rebuilt until 1921.
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.