The Da Ponte Fountain dates from 1666, replacing an older one on the same site. Its superstructure is in the shape of a bridge, surmounting an octagonal water basin surrounded by fifteen pilasters, each bearing the arms of local noble families who had contributed funds toward the fountain.
A subaquatic aqueduct connected the island of Koper to the mainland as early as the end of the 14th century. By the 16th century, the 10,000 inhabitants of the city were facing a water shortage, rainwater cisterns having become inadequate. In the 17th century, Niccolò Manzuoli recorded the city water supply, noting that a 2-mile distant spring at Colonna was piped to the island via wooden underwater tubes, some of which have been unearthed during excavations by modern archeologists.
The water spurts from four mascarons at the base of the arch. The fountain was used as a source of potable water until 1898.
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.