Sources of the Rhine

Lake Toma in the Swiss Canton of Graubünden is generally regarded as the source of the Rhine. Its outflow is called Rein da Tuma and after a few kilometers, it forms the Vorderrhein (English: Anterior Rhine; Romansh: Rein Anteriur). The course of this river is not particularly representative, after about two kilometers, its water is diverted into Curnera reservoir. The water is released at the Tavanase plant and flows into the Rhine at Ilanz. The river begins to be called Rhine in the vicinity of Chur, more specifically, at the confluence of the Vorderrhein and Hinterrhein (river) in Reichenau.

There are different criteria for the definition of tributaries, and by some definitions, irrespective of the official name, one strand or another may be called the source. Determining the source of the Rhine is difficult, because in the river system of the Anterior and Posterior Rhine, there are many headwaters of similar size. Apart from the common criterion of the (apparent or real) larger discharge, ongoing cartographic research allows us to determine the headwater with the greatest length, the largest catchment area or (occasionally) the highest source.

The direction of flow may be crucial to the nomenclature as may be the significance of the valleys as room for housing and transport. Both criteria are more appropriate to the Vorderrhein, since the Hinterrhein valley was hardly populated before the influx of the Walser.

The Swiss Federal Office of Topography and ETH Zürich indicate a point North of Lake Toma and the Rein da Tuma as the source of the Rhine (and also of the Vorderrhein), and as the source of the Hinterrhein a point in the upper Rheinwald valley, East of the Rheinwaldhorn.

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