The origins of the Calatubo Castle date back to some years before 1093, the year in which Roger I of Sicily defined the boundaries of the diocese of Mazara that included 'Calatubo with all its dependencies'.
In ancient times, around the castle there was the village of Calatubo, which based its business on the extraction of stones for water and wind mills from the quarries around the creek Finocchio, as mentioned by the Arab geographer Muhammad al-Idrisi in The Book of Roger, written in 1154.
The village of Calatubo was abandoned after the conquest by Frederick II and the castle lost its original function as a military fortress, turning into a farm. During this period, the castle joined warehouses, stables and other structures used for the administration of the agricultural fief of Calatubo.
Since the Middle Ages, because of its visibility, the Calatubo Castle had an important strategic role: it was part of a line of towers and forts along the coast from Palermo to Trapani; this defensive line was used to transmit light signals in case of Saracens' attack. In particular, the castle of Calatubo guaranteed the flow of information that took place between the outposts of Carini, Partinico and Castellammare del Golfo.
At the end of the nineteenth century in the second courtyard some warehouses were set up for the production of the wine 'Calatubo'.
The castle remained in good condition until the 1968 Belice earthquake. The use of the structure as a sheepfold and illegal excavations, which had as their targets the finds of the necropolis of the seventh century BC pertaining to the castle, have further ruined the castle. In 2007 it was bought by the municipality of Alcamo and over the past few years.
The Calatubo Castle is actually an architectural complex, consisting of the structure of the original castle that has undergone several changes over the centuries. This complex is large 150×35 meters and stands on a limestone rock that lies at an altitude of about 152 m above sea level and that dominate with its height the surrounding area. From the position of castle you can clearly see Mount Bonifato and the Gulf of Castellammare.
The castle is inaccessible on three sides due to the steep walls of rock on which it is built. The only practicable access is located in the west, which leads to the first line of defense of the castle via a ramp with large steps. From the first line of defense, which includes among other things a well, a church hall and other premises, you can arrive at a court which communicates with the second circle of walls through a portal, up to the third circle of walls, which comprises an oblong tower. Finally the core of the castle, located in the southern part of the fortress, is rectangular with an area of 7×21.50 m.
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.