The Monastery of the Cross was built in the eleventh century, during the reign of King Bagrat IV by the Georgian Giorgi-Prokhore of Shavsheti. It is believed that the site was originally consecrated in the fourth century under the instruction of the Roman emperor Constantine the Great, who later gave the site to king Mirian III of Kartli after the conversion of his kingdom to Christianity in 327 AD.
Legend has it that the monastery was erected on the burial spot of Adam's head—though two other locations in Jerusalem also claim this honor—from which grew the tree that gave its wood to the cross on which Christ was crucified.
Due to heavy debt the monastery was sold by the Georgians to the Greeks in 1685. It is currently occupied by monks of the Greek Orthodox Patriarchate of Jerusalem.
The remains of the crusader-period monastery forms a small part of the current complex, most of which has undergone restoration and rebuilding. The crusader section houses a church, including a grotto where a window into the ground below allows viewing of the spot where the tree from which the cross was (reputedly) fashioned grew. Remains from the 4th century are sparse, the most important of which is a fragment of a mosaic. The main complex houses living quarters as well as a museum and gift shop. The monastery library houses many Georgian manuscripts.
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.