France-Germany border
The border between the states of France and Germany has a length of about 450 km (280 mi).
The border can be traced back from the 17th century, and the various treaties following the Thirty Years' War starting with the treaty of Westphalia and Nijmegen, marking the Rhine as the frontier between France, and the different German states. The actual border as we know was determined after the revision acted at the Congress of Vienna in 1815. The border then changed after the French defeat during the Franco-Prussian war, where France was forced to yield Alsace-Lorraine to the new German empire in 1871. The territory was then restituted to France 48 years later after the treaty of Versailles in 1918. The border changed again in 1941 when the third Reich annexed de facto (without any international legal recognition nor treaty) the region. The actual border was re-established after the defeat of Nazi Germany in World War II.
The border follows the Upper Rhine from the tripoint (Dreiländereck) with the French-Swiss and the German-Swiss borders at Basel (47°35′24″N 7°35′20″E / 47.590°N 7.589°E), passing between Strasbourg and Offenburg. The Rhine forms the eastern border of Alsace on the French side, and the western border of Baden-Württemberg on the German side.
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