France–Germany relations of the further integration of the EU. They are sometimes described as the "twin engine" or "core countries" pushing for moves. A tram straddling the Franco-German border, across the river Rhine from Strasbourg to Kehl, was inaugurated on the 28th of April 2017 symbolising the strength of relation between the two countries. Both France and Germany track their history back to the time of Charlemagne, whose vast empire included most of the area of both modern-day France and Germany – as well as the Netherlands, Belgium, Luxembourg, Switzerland, Austria, Slovenia, and northern Italy. The death of Charlemagne's son Louis the
France–Germany relations President Joachim Gauck together marked the centenary of Germany's declaration of war on France by laying the first stone of a memorial in Vieil Armand, France, known in German as Hartmannswillerkopf, for French and German soldiers killed in World War I. Franco-German collaborative enterprises include; France–Germany relations The relations between France and Germany, since 1871, according to Ulrich Krotz, has three grand periods: 'hereditary enmity' (down to 1945), 'reconciliation' (1945–63) and since 1963 the 'special relationship' embodied in a cooperation called "Franco-German Friendship" (; ). In the context of the European Union, the cooperation between the two countries is immense