Rhine

The **Rhine** is a major river in western Europe. It is sourced in the Swiss Alps and flows northwards through Germany (where for some distance it forms the border with France) and The Netherlands, before discharging into the North Sea via the complex Rhine-Meuse-Schedlt Delta. It is the principal river of the Rhine Basin.

## Course

### Alpine Rhine

The uppermost reaches of the Rhine are commonly referred to as the "Alpine Rhine". Here, the river has two main sources: the more westerly Anterior Rhine and the more southerly Posterior Rhine. The two rivers combine at Reichenau and from there flow as the Rhine proper towards Lake Constance.

As the river leaves Reichenau behind, the valley floor broadens and the river becomes artificially straightened. At Domat, it is joined by the Mulinbach and at Chur by the Plessur, before bending northwards. The Rhine meets the Landquart at Landquart and soon turns again to the northwest. At Bad Ragaz, the river is joined by the Mühlebach and the Tamina, then proceeds towards Sargans. It is here that the valley branches in two and a natural dam, only a few metres high, prevents the river from flowing northwest into the Seetzal valley and the Aare's drainage basin. The Rhine instead bends sharply to the northeast and picks up the Vilterser-Wanser Kanal (carrying water from the Saar among other natural streams). The channel undergoes another course correction and bends to the north, forming the border between Switzerland and Lichtenstein. The river has at this point become flanked by artificial waterways such as the Vaduz and Werdenburger "Binnenkanals" to manage local drainage. Turning again to the northeast and now forming the Swiss-Austrian border, the Alpine Rhine is joined by its largest tributary, the Ill, as well as the Frutz shortly thereafter. The section of the Rhine immediately upstream of Lake Constance has undergone substantial regulation; a former meander at Diepoldsau has been artificially bypassed and the entire old course from Lustenau to its former delta (now the Alter Rhein) has been abandoned and modified in favour of a more easterly route. The Dornbirner Ach has also been diverted to run parallel to the current channel before emptying into the lake. The Rhine itself is channeled over 3 kilometres into the middle of the lake in order to reduce sedimentation.

#### Lake Constance

The Lake is comprised of two primary lobes - the larger Obersee (upper lake) and smaller Untersee (lower lake), with the natural channel connecting the two referred to as the Seerhein. The water body largely forms the border between Switzerland and Germany, as does its outflow, the High Rhine. Aside from the artificially diverted Alter Rhein, the lake lacks any substantial tributaries on its southern fringe and so its remaining inflow is recieved along its northern bank (or right bank from the perspective of the Rhine) from the following rivers (anti-clockwise, from the Rhine inflow):

* Dornbirner Ach (west of Bregenz)
* Bregenzer Ach (at Bregenz)
* Leiblach (at Unterhochsteg)
* Argen (at Langenargen)
* Schussen (north of Langenargen)
* Rotach (at Friedrichshafen)
* Seefelder Aach (at Oberuhldingen)
* Stockacher Aach (north of Bodman)
* Radolfzeller Aach (Untersee, south of Radolfzell)

### High Rhine

At Stein am Rhein, the Rhine exits the Untersee and flows westwards. The landscape is no longer Alpine and is instead relatively flat with scattered hills. The Biber joins at Rheinklingen and the river proceeds towards the town of Schaffhausen, where it turns abruptly to the south and shortly cuts over hard limestone bedrock, forming the Rheinfall (the only waterfall directly on the course of the Rhine and one of the most powerful in Europe). Now leaving Schaffhausen, the Rhine continues southwards through a series of wide meanders, before meeting the Thur, turning sharply again (at its confluence with the Töss), and resuming its westward course once more. Shortly downstream, the river is joined by the Glatt and approaches the city of Waldshut-Tiengen. Here, the Rhine is joined in quick succession by the Wutach (from the north) and the Aare (from the south), the latter being by far the largest tributary yet and comparable in size to the entirety of the Alpine and High Rhine up to this point. With the Rhine now doubled in magnitude, the river bends slightly to the southwest and picks up the Alb, before return to its westward course. At this point, the High Rhine is bounded on the south by the Jura Mountains (of which part are drained by the Sissle) and on the north by the Black Forest (of which part is drained by the Wehra). The final Jura tributaries, the Ergolz and the Birs join at Kaiseraugst and outer Basel, respectively. The city of Basel marks the point where the Rhine ceases to form the border between Germany and Switzerland, and transitions to the Upper Rhine.

### Upper Rhine

As the Rhine gently meanders through Basel, joined by the Wiese along the way, it gradually turns to the northwest, then further again to the north as it exits the outskirts of the city. Upon completion of this great bend, the river emerges onto a wide plain over 30 km in width. This marks the floor of a large rift valley bounded on the west by the low French Vosges mountains and on the east by the Black Forest in Germany. It is the Rhine itself that once again marks the border between these two countries. Owing to yazoo stream the Ill, the river has few left-bank tributaries of much significance at this point until Strasbourg, therefore much of the new runoff will be from streams from the Black Forest. The first of these is the Sulzbach, which joins near Hartheim am Rhein, and the second is the Möhlin, which joins at Breisach. The larger Elz