Helme church parish was first mentioned in 1329 during a Lithuanian raid. Most of the neighbouring land was fiefed in the 15th–16th centuries. Livonian Order castle in Helme (Ordensburg Helmet) was probably built in the first half of the 14th century.
The site on a steep hill is belived to have been used as a stronghold earlier by Sackalians in the Ancient Estonia. By its ground plan the order castle was 120×60 m oval shaped structure, surrounded by two moats. There was a borough beside the castle in the Middle ages, it was mentioned until the 17th century. The castle was destroyed by the Swedes during the Russo-Swedish War in 1658. Nowadays only parts of the walls with high window holes have survived.
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.