The Castle of Mercato San Severino is the second-largest castle in Italy and was founded after 1067 by a Norman knight named Turgisio Sanseverino. The appearance of the castle today has been particularly influenced by the Angevin period. The settlement is marked by three walls: a first nucleus that includes the palatium and the so-called piazza d'armi (army square), and other rooms. The walls of the first enclosure continue south, surrounding a Franciscan convent, the village, and the corresponding church.
The second enclosure with its semicircular towers extends eastward, and it is connected to the last enclosure from the Angevin-Aragonese era, with a triangular perimeter that has a round tower at its vertex. The original size of the site was approximately 350 by 450 meters, with a total area of 157,500 square meters, equivalent to three football fields.
The third enclosure, at a lower elevation, extends eastward with a layout called 'a sperone,' and at its highest point, there is a round tower with three typical Angevin-era gun ports.
The castle was initially owned by the Sanseverino family but was eventually abandoned due to the involvement of one of its members in the Barons' Conspiracy against Ferrante. As a result, Ferrante confiscated the castle from its owners and only returned it after several years, by which time it had lost most of its military characteristics. The castle still partially preserves the chapel and the church. Saint Thomas himself visited this castle to visit his sister, Teodora, who was married to a Sanseverino. The future saint stayed at the Dominican convent. Coins, ceramics, arrowheads, and many other artifacts have been found inside the castle.
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.