Geological Hiking Trail up to the Knappa Gruaba

 You have reached plate 14 which describes the youngest layers in the Bartholomaeberg area – the Koessen formation.  On the way back to Bartholomaeberg, you pass through the Earth’s history starting from the youngest and going to the oldest layers, from a time 100 million years ago to the 300 million year old Upper Carboniferous sediments deposited on the crystalline basement, and built by the 1.5 billion year old debris of an older mountain chain which underwent several melting processes.

If you want to take a short cut, descend in a southerly direction moving towards the Silbertal valley and follow the marked trail directly to plate 16 – Raibl formation - at the location of Blengalang.

The Geology Hiking Trail leads you in the direction of the Kloster Valley, first through the meadow with the Koessener formation in the underground, and next through the layers of Hauptdolomite on the Kristberg - Falla - Latons trail.  If you take this path westwards you will reach the Bomatschies Forest sink holes in 20 minutes.

On the trail travelling eastwards to Kristberg you reach plate 15, Hauptdolomite – Plattenkalk, on a big rock block, and 10 minutes after that, the Falla view point.

Here you have another great view down into the Kloster Valley, and into the deep, rough gully of the Rotrüfetobel, a feared wild torrent in the Raibl formation.

From here you will come to the small medieval church that was built by miners on the Kristberg and then the cable car railway on a marked trail via Ganzalaeta The Geological Educational Hiking Trail descends through the mountain pine and spruce forest to the alpine meadows of Blengalang. Here you find plate 16 at the southern slope of a hollow describing the Raibl formation. The exceptionally diversely formed landscape with its synclines, opposite backs and steep steps are due to different layers of varying strength within the Raibl formation, which you cross going downhill to the road along the Almazu which is a fence on the mountain meadow.

Shortly before you reach the road, the trail crosses the sand dolomite, which can be crushed with your bare hands, and the sand chalks of the Raibl formation.

Now the Geology Hiking Trail follows the road along the fence a bit west of Lake Fritza.
Take a look at the lakes south of the path.  The Tora, Fula and Fritza lakes, are all embedded in distinct valley hollows on the slope to Silbertal.

These valley hollows with their lakes exist thanks to the Reichenhaller Rauhwacke of the Punt-la-drossa formation’s low resistance to weathering, leaching and erosion.

This rock, which originated from sea lagoons that separated due to evaporation of the sea water, was mentioned at the beginning of the hike. The hollows and their accompanying walls on the valley side also mark a longer recessional stage of the ice-age Ill-glacier.

Plate 17 in the slope embankment along the road from Amans Legi to Lake Tora describes the Arlberg layers in their typical sequence; west of Lake Tora, plate 18 informs you about  the Partnach layers up to Lake Fula and plate 19 shows the muddle limestone of the Alpiner Muschelkalk formation which is typical of this area. At the intersection east of Lake Fritzen, plate 20 is mounted on sandstone and sandy marl from the punt-la-drossa formation. Plate 21 describes the red layers of the Alpine Verrucano. Southwest of Lake Fritzen near plate 22, which has information about the sediments of the Upper Carboniferous period, you leave the road and follow the marked trail to Knappa Gruaba crossing the meadows and overgrown mining wastes. Then you walk past the caved-in adit openings of the medieval galleries. In the recently established mining building you can get information about the opening hours and guided tours of the model mining-tunnel. At the other side of the swampy meadow at the edge of the forest, plate 23 offers more orientation and information.