Swiss-German border

The border between the modern states of Germany and Switzerland extends to 362 km, mostly following the High Rhine between Lake Constance and Basel.

Much of the border is within the sphere of the Zurich metropolitan area and there is substantial traffic, both for commuting and for shopping across the border; line S22 of the suburban Zürich S-Bahn even running across German territory, and the Swiss municipality of Kreuzlingen forming part of the conurbation of German Constance. Similarly, Basel metropolitan area includes territory in both France and Germany.

The High Rhine has had the character of the northern border of the Old Swiss Confederacy since the Swabian War and the accession of Basel in 1499–1501, dividing the Swiss Confederacy from the Swabian Circle of the Holy Roman Empire; with the Peace of Westphalia of 1648, the border acquired the status of an international border de jure.

With minor changes (such as the acquisition of Rafzerfeld in 1651), it remained unchanged since, even throughout the Napoleonic era when it divided two French client states (Cisrhenian Republic and Helvetic Republic) and later the Confederation of the Rhine from the restored Swiss Confederacy, and eventually the German Confederation from modern Switzerland. The border persisted even during the Nazi era (although with the Anschluss of Austria, the German-Swiss border technically included the Austrian-Swiss border from 1938 and until the formation of the German Federal Republic in 1949).

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Wikipedia