Forte San Giovanni was built between 1640 and 1644 just above the point where the valleys of rivers Pora and Aquila meet with the aim of strengthening defenses. The fort was adapted to the geographic topography and enclosed the ancient medieval tower linking the Finalborgo walls on Becchignolo hill. The work was directed by Ferdinando Glazer. This tower was recorded by the historian Filelfo and portrayed in a drawing of 1571.
The building developed with a pincer-shaped façade facing south, with high crowned walls with no openings, surmounted by a low parapet, and with suspended look-out towers on each corner. The fortress underwent other modifications directed by Spanish engineer Gaspare Beretta between 1674 and 1678. It was abandoned by the Spanish in 1707 and, under the domination of Genoa in 1713, it was partially destroyed. In 1833 it became a prison.
Since 1960 it has been public property and it has recently been completely restored.
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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.