Alpine Rhine

The Alpine Rhine Valley () is a glacial alpine valley, formed by the Alpine Rhine ( ), the part of the Rhine between the confluence of the Anterior Rhine and Posterior Rhine at Reichenau and Lake Constance. It covers three countries, with sections of the river demarcating the borders between Austria and Switzerland and between Liechtenstein and Switzerland. The full length of the Alpine Rhine is 93.5 km.

From Reichenau, the Alpine Rhine flows east, passing Chur and turning north, before it turns north-east at Landquart, and then roughly north, east of Sargans. From here, the Alpine Rhine forms the border between the canton of St. Gallen of Switzerland on the left, west side, and the Principality of Liechtenstein on the east side. About further down, the Rhine then meets the Austrian federal state Vorarlberg and finally flows into Lake Constance, south of Lindau (Germany), which is no longer part of the Rhine Valley. The Swiss-Austrian border follows the historical bed of the Rhine, but today the river follows an artificial canal within Austria for the final , parallel to the also canalised Dornbirner Ach. The border also still follows the old river bed at Diepoldsau.

The Rhine Valley's upper third has the character of an Alpine valley, enclosing a bottom plain of about across. Downstream of Vaduz, the valley widens considerably, developing into a broad plain, measuring some across at its lower end along the southeastern shores of Upper Lake Constance. The latter is separated from the Lower Lake Constance by a short stretch of the Rhine, called the '' Seerhein'' (). From the point of the Rhine's emergence from Lower Lake Constance, it is known as the High Rhine ().

Right tributaries of the Alpine Rhine are the Plessur in Chur, the Landquart in the town of the same name, the Ill and Frutz on the ''Upper Land'' of the Austrian plain near Feldkirch. Several rivers in Liechtenstein drain into a canal, which carries the water to the Alpine Rhine. The Alpine Rhine has no major left tributaries; creeks joining it from the left are the Oldisbach at Chur, Cosenz at Untervaz, Säge at Tardisbrücke, Tamina at Bad Ragaz, Saar at Trübbach, Tobelbach at Buchs, Simml at Gams. Though all left tributaries in the St. Gall Rhine Valley are collected by the Rheintaler Binnenkanal, which flows into Lake of Constance by '' Alter Rhein'', and never meets the Alpine Rhine anymore.

Geography

The Alpine Rhine Valley is flanked by the Alps and its mountain ranges (especially Alpstein, Plessuralpen, Rätikon Calanda, the Albula Alps and the Glarner Alps), some higher than . The highest mountain, Ringelspitz, commences next to Tamins. At , it is the highest peak of the canton of St. Gallen, bordering the valley to its southeast.

Valley

Geographical parts of the Alpine Rhine Valley are:

Upper half:
* Chur Rhine Valley, or Grisonian Rhine Valley (): The name refers to the town of Chur, or its canton Graubünden, respectively. It starts at Rhäzüns/ Bonaduz and ends east of Sargans (SG).

Lower half:
:To the north, the Bündner Rheintal crosses into the Rhine valley between Sargans and Lake of Constance, where it largely forms the border between the canton of St. Gallen on the west side and Liechtenstein and Austria on its east side. The valley is simply called the ''Rhine Valley'' on either side. The Swiss sometimes also call it the ''St. Gall Rhine Valley'' in order to distinguish it from its upper half.
:* St. Gall Rhine Valley (): On its western side, the Rhine Valley is politically further divided into Werdenberg (Wahlkreis) and Rheintal (Wahlkreis), though geographically it is separated by the ''Hirschensprung'' near Rüthi (SG).
:*Eastern side:
:**On its eastern side, the upper half of the valley is called the Liechtenstein Rhine Valley ().
:** Vorarlberg Rhine Valley (): The lower half is also called the ''Vorarlberg Rhine Valley'', since it belongs to the Austrian federal state Vorarlberg. It is further divided into an upper and lower part and referred to as the ''Upper and Lower Lands'' (). The Lower Lands, sometimes also called , stretches from the shores of Lake Constance to the small hill ''Kummaberg'' to the south, the upper part lies south of it.

Aussicht vom Pizalun Richtung St. Luzisteig.jpg, The end of the Grisonian Rhine Valley. In front: Bad Ragaz on the left and Maienfeld on the right.
Staubernbaehnli01.jpg, St. Gall Rhine Valley (right of the river) and Liechtenstein Rhine Valley (seen from Mt. Stauberen ()
Churer Rheintal from Montalin.jpg, center, upright=2.5, Chur Rhine Valley with Chur

Alpine Rhine

The Alpine Rhine begins in the centre of the Swiss canton of Grisons (), and later forms the border between Switzerland to the west and Liechtenstein to the east, and later between Switzerland and Austria. The river is formed near Tamins- Reichenau by the confluence of the rivers Anterior Rhine () and the Posterior Rhine (). Its mouth is at the Upper Lake Constance. It descends from an elevation of . The river makes a distinctive turn to the north near Chur. At Landquart it turns north-east and then to the north around the Fläscherberg, east of Sargans. Near Sargans a natural dam, only a few metres high, prevents it from flowing further to the north-west into the open valley, called Seeztal, and then consequently through Lake Walen (and further to Lake Zurich into the river Aare).

Besides the ''Vorderrhein'' and ''Hinterrhein'', the Apline rhine has only a few other larger tributaries. Its main right tributaries are the Plessur (in Chur), the Landquart river in Landquart, the Liechtenstein inland canal in Liechtenstein (near the northern end of the country), and the Ill and Frutz in Austria (Vorarlberg). Main left tributaries, all located in Switzerland, are the Tamina (in Bad Ragaz) and the Saar (in Trübbach).

The mouth of the Rhine into Lake Constance forms an inland delta. The delta is delimited in the west by the '' Old Rhine'' and in the east by a modern canalized section. Most of the delta is a nature reserve and bird sanctuary and has been designated as a Ramsar site