San Nicolás church dates back to medieval times, although it has been much altered over the centuries. It is named in the Law of Madrid of 1202 as one of the oldest parishes in the city. Today it is the oldest church in Madrid, after the demolition of the Church of Santa Maria de la Almudena. Archaeological remains suggest that the church and its bell-tower may have been part of a former mosque. It was likely constructed during the 12th century. The nave and chapels were renovated in the 17th century.
By the 19th century, this church was poor in resources and parishioners. The parish was joined to that of El Salvador in 1805. For a time, the building was abandoned till the church was ceded in 1825 to the Third Order of Servites. When the nearby church of El Salvador was destroyed in 1842, this church gained its former status as a parish church.
In the year 1891 the parish was relocated to a church that had been Anton Martin Hospital in Atocha street, today the Parish of San Nicolas and San Salvador, leaving the old building as the church of 'St. Nicholas of the Servites', a name derived from the Servite Order, which still owns it.
At the end of century profile interventions have been implemented, the main one being held in 1983. In some of these interventions was the replacement of the stone, he must be very poor, in the apse, where they appreciate different finishes to the original stone.
The most interesting feature of this temple is undoubtedly its tower, dating from the 12th century except the Herrerian style spire tops, made of slate for the 18th century. It has a square and is constructed of brick decorated with blind arches. The brick has dimensions of 30 x 15 cm in the lower parts, but it was the brick bell tower area are smaller and of a different hue. This tower possibly corresponds to one of the Arab minarets preserved in the city. The tower was transformed in the 14th century, when it changed the cover, which was subsequently replaced by the spire.
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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.