Hinterburg is one of the four castles in a string along the Neckar River, built by the von Steinach family in the 1100s. It is the oldest of the four, serving a strategic purpose in allowing the lords to observe the Neckar and Steinachtal. One of the earliest records mentions Bligger von Steinach, c. 1160. His son, Bligger II, who was also a famous minstrel of the time, added much of the outer wall that helped drastically improve the castle's defensive posture. At one time it also had a dry moat with a drawbridge. The castle continued to be used up until the 1600s, largely in the service of the Elector Palatine. Afterwards it began to decay from neglect as it lost its importance in the era of cannon. There is no indication that it was ever seriously besieged.
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.