Originally there was a chapel situated on the site of the current Aa-kerk church. This chapel was devoted to Mary and to Saint Nicholas, the patron of the bargees who cast off the vessels at the Westerhaven.
In 1247, the chapel became the parish church and was named Onze Lieve Vrouwe ter Aa (Our Lady at the Aa) - Aa being the nearby river. Groningen had two centers at the time. One of them was around the chapel. Here lived the fishermen and the traders. Between 1425 and 1465, the chapel was changed into a brick church with a transept.
Images of the Siege of Groningen in 1672 show Der Aa-kerk without the top of the tower. After the war a new wooden tower top was built. On 23 April 1710, the tower spontaneously collapsed killing two people. In 1711, a new tower was built.
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.