sources of the Rhine

The source of the River Rhine is generally regarded to be Lake Toma, in the Swiss canton of Grisons (Graubünden). The lake's outflow, the Rein da Tuma, subsequently becomes the Anterior Rhine (Sursilvan: Rein Anteriur, Vorderrhein), which later confluences with the Posterior Rhine (Sutsilvan: Ragn Posteriur, Hinterrhein) to form the Rhine (Alpine Rhine). Because the tributary systems of the Rhine differ only slightly in length, discharge and the size of their drainage areas, it is difficult to pinpoint a single source of this major European river.

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