Basel is a city in northwestern Switzerland on the river Rhine. Basel is Switzerland's third-most-populous city (after Zürich and Geneva) with about 180,000 inhabitants.

Located where the Swiss, French and German borders meet, Basel also has suburbs in France and Germany. As of 2016, the Swiss Basel agglomeration was the third largest in Switzerland with a population of 541,000[4] in 74 municipalities in Switzerland (municipal count as of 2018). The initiative Trinational Eurodistrict Basel (TEB) of 62 suburban communes including municipalities in neighboring countries, counted 829,000 inhabitants in 2007.

The official language of Basel is (the Swiss variety of Standard) German, but the main spoken language is the local Basel German dialect.

Düsseldorf is the capital and second-largest city of the most populous German federal state of North Rhine-Westphalia after Cologne, as well as the seventh-largest city in Germany. with a population of 617,280. At the confluence of the Rhine and its tributary Düssel, the city lies in the centre of both the Rhine-Ruhr and the Rhineland Metropolitan Regions with the Cologne Bonn region to its south and the Ruhr to its north. Most of the city lies on the right bank of the Rhine (as opposed to Cologne, whose city centre lies on the river's left bank). The city is the largest in the German Low Franconian dialect area (closely related to Dutch). "Dorf" meaning "village" in German, the "-dorf" suffix (English cognate: thorp) is unusual in the German-speaking area for a settlement of Düsseldorf's size.

Düsseldorf is the capital and second-largest city of the most populous German federal state of North Rhine-Westphalia after Cologne, as well as the seventh-largest city in Germany. with a population of 617,280. At the confluence of the Rhine and its tributary Düssel, the city lies in the centre of both the Rhine-Ruhr and the Rhineland Metropolitan Regions with the Cologne Bonn region to its south and the Ruhr to its north. Most of the city lies on the right bank of the Rhine (as opposed to Cologne, whose city centre lies on the river's left bank). The city is the largest in the German Low Franconian dialect area (closely related to Dutch). "Dorf" meaning "village" in German, the "-dorf" suffix (English cognate: thorp) is unusual in the German-speaking area for a settlement of Düsseldorf's size.