Las Siete Calles or Casco Viejo are different names for the medieval neighbourhood of Bilbao. The names mean Seven Streets or Old Town respectively and it used to be the walled part of the town until the end of the 19th century.
The name come from the oldest part of the neighbourhood which included exactly 7 streets and some much more narrow alleys connecting them, called cantons.
The old quarter is an area of incredible interest in Bilbao, and it is one of the most visited areas of the city
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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.