The Wissembourg Gap (French: trouée de Wissembourg, German: Weißenburger Senke) is a corridor of open terrain, approximately six kilometres (3.7 miles) wide, between the hills of the Palatinate Forest to the west and the Bienwald forest (and beyond that the Upper Rhine) to the east. It marks the border between the Palatinate to the north and Alsace to the south, and by extension between Germany and France.[1] The Gap is dominated by the French town of Wissembourg, from which it takes its name. The average altitude of the land in the corridor rises from 150 metres by the Bienwald to 250 metres by the Palatinate Forest.
Because of the Wissembourg Gap's position on the Franco-German border, it has frequently been a favoured route for military invasions, notably during the War of the Austrian Succession, the French Revolutionary Wars, the Franco-Prussian War, and the Second World War.