Ruppertstein Castle history began in 1198 with the purchase by Count Henry I of Zweibrücken of the hill on which it was built. Little is known of the castle, which was probably built in the 13th century. It was either destroyed in 1525 during the Palatine Peasants' War or had been allowed to fall into ruins by then.
Around 1900 a stone stairway was built on the rocks in order to reach the terrace of the rock on which the castle stood, in order to use it as a viewing point. This stone stairway was refurbished in 2007 by the Pirmasens-Land municipal authorities. A wooden stairway may originally have been used to access the castle.
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.