Fortress church

A fortress church (German: Kirchenburg) is particular type of church that, in addition to its religious functions is also used by the local population as a retreat and defensive position, similar to a refuge castle. A fortress church usually implies that the church is enclosed by its own fortifications, such as curtain walls and defensive towers. By comparison, a church with simple defensive features, such as battlements and embrasures on the church itself, is usually just referred to as a fortified church.

The fortress church is typically surrounded by defensive walls equipped with wall towers and wall walks. It is a development of the fortified churches, whose defensive walls were also the actual walls of the church. However, the terms are often used interchangeably and there is often no clear distinction. However, generally a fortified church is a single building, whereas a fortress church is a building complex.

In the Early Middle Ages, former bishop's seats, especially in recently Christianised regions like Saxony, were designed as fortress churches. There they were referred to as a Domburg or "cathedral castle".

Fortress churches are especially common in Franconia, South France and Transylvania. Particularly in Transylvania, a historic German settlement area in Romania, there are well over a hundred fortress churches, of which seven have been designated as UNESCO World Heritage Sites (Birthälm/Biertan in 1993, Kelling/Calnic, Wurmloch/Valea Viilor, Dersch/Darjiu, Deutsch-Weißkirch/Viscri, Keisd/Saschiz and Tartlau/Prejmer in 1999). They were built and maintained in order to defend against successive Turkish invasions.

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