On a north-south route of 70 km you get a cross-section of all Alpine landscapes.The Bregenzerwald to the north, here we find the Pfänder - is part of the Alpine foothills (molasse belt). To the south, in the low region of the Bregenzerwald, we find the Helvetikum (Hoher Freschen, Kanisfluh, Mittagsfluh, Hohen Ifen) and the Fysch zone (Grosses Walsertal). Molasse, Helvetikum and Fysch zone consist of easily eroding, soft rocks. Thus the landscape is rounded and up to high altitudes covered by vegetation. The limestone Alps in contrast are precipituous rocks (Lechtaler Alpen and Rätikon). South of the Klostertal valley rise the Central Alps with the Verwall and the Silvretta group.
Here we find the highest peak of Vorarlberg, the Piz Buin (3312 m). In the Rhine valley the glaciers of the Ice Age carved into a depth of several hundred metres.
Through valleys of the Rätikon (Gamperdonatal, Saminatal), firn fields and
moraines and terracettes are impressive remains of the Ice Age. At that time
Lake Constance ranged deep into the Rhine valley to the south and to the west
up to Sargans. In the course of 10,000 years the original Lake Constance dried out.
In the past 100 years, after the bendy river was controlled, sediments and river
gravel have gone directly into the lake and gather. In this way the Rhine delta
grew up to 200 metres into the lake.