Zwinger (fortification)

A Zwinger (German pronunciation: [ˈt͡svɪŋɐ]) is an open area between two defensive walls that is used for defensive purposes.Zwingers were built in the Middle Ages and Early Modern Period to improve the defence of castles and town walls. The term is German and usually left untranslated. However, it is sometimes rendered as "outer courtyard" presumably referring to the subsequent role of a Zwinger as a castle's defences became redundant and it was converted into a palace or schloss, however, this belies its original purpose as a form of killing ground for the defence. The word is linked with zwingen, "to force", perhaps because the Zwinger forced an enemy to negotiate it before assaulting the main defensive line. Essenwein states that the "main purpose of this feature was so that the besieging force could not reach the actual castle wall very easily with battering rams or belfries, but had to stop at the lower, outer wall; also that two ranks of archers, behind and above one another, could fire upon upon the approaching enemy"

The Zwinger of a castle is sited in front of the main curtain wall and is enclosed on the outer side by a second, lower wall, known as the Zwinger wall (Zwingermauer). If attackers succeed in getting past the Zwinger wall, they would be trapped in the Zwinger and were an easy target for the defenders on the main wall (Hauptmauer). Further progress was thus seriously impeded.

In central Europe most Zwingers were built in front of older castle walls as a later addition and reinforcement of the defences.

The Zwinger in front of a town gate is a fortified area between the main gate and the outer gate of a medieval town gateway system. Town gates were often built in the shape of a gate tower, with a second, and sometimes even a third, gate in front of it (so-called double or triple gate systems). In front of the town walls in the area of the town gates there was usually a second wall in which the outer gate was located. An enemy who had breached the outer gate and penetrated the Zwinger would find himself in an enclosed area with very little scope to exploit his initial success. By contrast, the defenders retreating behind the main town walls could easily engage the enemy below them in the killing ground of the Zwinger.

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