The Reuss, the Aare, the Rhine and Koblenz in Switzerland

2 September 2023

Koblenz (canton of Aargau) is the site of the Aare, the Reuss and the Rhine confluence. The Aare is the largest tributary of the Rhine, with more cubic metres of water per second than the Main or the Moselle at Koblenz in Germany.

The Rhine and the Reuss originate in the Gotthard massif. The source of the Aare is the Oberaar glacier in the Bernese Alps. It then flows through Lake Thun and Brienz, Bern and the canton of Solothurn.

It was canalised in the Correction of Jurassic Waters in the nineteenth and twentieth centuries. After absorbing the Limmat, it enters the Rhine near Koblenz.

The Aare is the longest river flowing exclusively on Swiss soil, measuring 295 kilometres.