Читать книгу The Adlerweg. The Eagle's Way across the Austrian Tyrol онлайн

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The enduring legacies left behind by the retreating glaciers are characteristic deep U-shaped valleys and morainic lakes. Throughout the walk you will be able to trace old glacial flows, from smooth bowl-shaped cirques surrounded on three sides by high jagged mountains, down stepped valleys blocked by terminal moraines containing either morainic lakes or the dried up beds of earlier lakes. The descent from Birkkarspitze (Stage 11) is almost a geography lesson with every kind of glacial feature on show.

The receding glaciers stripped much of the topsoil, leaving large areas of smooth limestone exposed. The steady slow erosion of this bare limestone by acidic rainwater causes limestone pavements to be formed. While karst pavements are seen on the surface (notably above Zireineralm, Stage U6), most karst features are hidden below ground in a series of sinkholes and cave systems. Zireinersee lake (Stages 7 and U6) is a karst lake with no visible outlet, while the Hundsalm Eishohle cave (Stage 4) is part of a karst cave system.