Posterior Rhine

The Posterior Rhine is a river in Switzerland, and is one of the two main sources of the Rhine. It begins in the southern Glarus Alps and flows northwards towards Reichenau, where it meets its counterpart, the Anterior Rhine.

Course
The Posterior Rhine begins broadly parallel to, but further south than the Anterior Rhine, along a valley known as the Rheinwald in the Viamala region of the Swiss canton of Grissons. There are relatively few features of note along this initial section of the river (aside from the Sufnersee reservoir) and it is only after the Posterior Rhine passes through the Rolfa gorge that it is joined by a tributary of significant size - that being the Avers Rhine. The river immediately turns to the north and enters the Schams valley, where the landscape takes on a more agricultural character. Exiting the Schams, the Posterior Rhine passes through another gorge, the Viamala, after which it is joined by the Nolla. Now in the Domleschg valley, the mountain stream meets its largest tribtuary, the Albula, and enters a channelized section. The now more regulated river receives water from additional tributaries including the Coznerbach and the Tomilserbach, before briefly regaining its natural character as the valley floor narrows. It is here that the Posterior Rhine meanders towards Reichenau and meets its sister stream.