Ietas was an ancient town in the modern comune of San Giuseppe Jato. Ietas was mentioned by Philistus as a fortress, and it is called by Thucydides a fortress of the Siculians, which was taken by Gylippus on his march from Himera through the interior of the island towards Syracuse. It first appears as an independent city in the time of Pyrrhus, and was attacked by that monarch on account of its strong position and the advantages it offered for operations against Panormus; but the inhabitants readily capitulated.
In the First Punic War it was occupied by a Carthaginian garrison, but after the fall of Panormus drove out these troops and opened its gates to the Romans. Under the Roman government it appears as a municipal town, but not one of much importance. The Ietini are only noticed in passing by Cicero among the towns whose lands had been utterly ruined by the exactions of Verres; and the Ietenses are enumerated by Pliny among the populi stipendiarii of the interior of Sicily. Many manuscripts of Cicero read 'Letini', and it is probable that the Λῆτον of Ptolemy is only a corruption of the same name. The town minted coins in antiquity, examples of which survive.
The position of Ietas is very obscurely intimated in ancient sources, but it appears from Diodorus that it was not very remote from Panormus, and that its site was one of great natural strength. Silius Italicus also alludes to its elevated situation. Fazello assures us that there was a mediaeval fortress called Iato on the summit of a lofty mountain, about 25 km from Palermo, and 20 km north of Entella, which was destroyed by Frederick II at the same time as the latter city; and this he identified as the site of Ietas. The mountain is still called Monte Iato, though formerly known as Monte di San Cosmano, from a church on its summit.
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.