The Haut-Koenigsbourg castle dominates the plain of Alsace, wedged between the Vosges on the west and the Black Forest on the east. Both mountainous massifs were born from the collapsing of the Rhine ditch, filled by a sea during the Cenozoic era (66 million years ago). When retreating, the water gave way to a large plain of sediments favorable to the growth of vines. This conducive environment led the inhabitants of the region to dedicate themselves to its culture since the Celts and Romans. Today, wine-growing is still the main activity among the villages of the Alsace plain.