St. John's Church (Sint-Janskerk), named after St.John the Baptist, was originally built as a baptistery for the St. Servatius Chapter of Maastricht. In 1633, after a period in which it functioned as an autonomous parish church, it came into the possession of the Dutch Reformed Church, established in 1632. This as a result of the capture of Maastricht from the Spanish army in 1632 by the troops of the Seven United Provinces of the Netherlands under the command of Prince Frederik Hendrik of Orange. After the establishment of a state-church, i.e. the Dutch Reformed Church, all catholic churches had become protestant in the regions already conquered.
The Prince Bishop of Liège, the Duke of Brabant and Prince Frederik Hendrik agreed that in Maastricht in principle only smaller chapels should be handed over to the protestants. The bigger churches remained catholic, which was exceptional from a national point of view. However, already in 1633 the protestant chapels proved to be too small and after new discussions two churches, one of which was St.John's, came into the possession of the protestants. The first service of the Dutch Reformed Church took place on the 1st of January, 1634.
Since 1987 the church has been in the use of the 'Protestantse Gemeente St. Jan', a federation of two different reformed communities.
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.