Alpine Rhine

The Alpine Rhine Valley (German: Alpenrheintal) is a glacial alpine valley, formed by the part of the Alpine Rhine (German:  Alpenrhein ) between the confluence of the Anterior Rhine and Posterior Rhine at Reichenau and the Alpine Rhine's mouth at Lake Constance. It covers three countries and the full length of the Apine-Rhine is 93.5 km.

From Reichenau, the Alpine Rhine flows east, passing Chur and turning north, forms the border between the canton of St. Gallen of Switzerland on the left, west side and Principality of Liechtenstein on the east side. The Swiss-Austrian border follows the historical bed of the Rhine, but today the river follows an artificial canal within Austria for the final 5 kilometres (3 mi). The Rhine then crosses Vorarlberg, Austria and flows into Lake Constance, south of Lindau (Germany) which is no longer part of the Rhine-Valley.

The Rhine Valley in this area extends to about 80 kilometres (50 mi). Its upper third has the character of an Alpine valley, enclosing a bottom plain of about 1 to 4 kilometres (0.6 to 2.5 mi) across. Downstream of Vaduz, the valley widens considerably, developing into a broad plain, measuring some 10 kilometres (6 mi) across at its lower end along the southern shores of Lake Constance. From the point of the Rhine's emergence from Lake Constance, it is known as High Rhine.

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