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.References:
The Erfurt Synagogue was built c. 1094. It is thought to be the oldest synagogue building still standing in Europe. Thanks to the extensive preservation of the original structure, it has a special place in the history of art and architecture and is among the most impressive and highly rated architectural monuments in Erfurt and Thuringia. The synagogue was constructed during the Middle Ages on the via regia, one of the major European trade routes, at the heart of the historical old quarter very close to the Merchants Bridge and the town hall. Many parts of the structure still remain today, including all four thick outer walls, the Romanesque gemel window, the Gothic rose window and the entrance to the synagogue room.
After extensive restoration, the building was reopened in 2009. On display in the exhibition rooms is an collection of medieval treasures discovered during archaeological excavations. This includes 3,140 silver coins, 14 silver ingots, approx. 6,000 works of goldsmithery from the 13th and 14th centuries and an intricately worked wedding ring of the period, of which only two others are known to exist anywhere in the world. A mikveh (Jewish bath) has been excavated close by (13th/14th century). The Old Synagogue, the Small Synagogue and two Jewish cemeteries together form a network of historical buildings and sites which vividly portray the role of Jewish life in the history of Erfurt.