Tyssaer Wände

View of the Große Tyssaer Steine
Bizarre weathering at the Steinpilz

The Tyssaer Wände (Czech: Tiské stěny, literally "Tyssa Walls") are a well-known group of rocks in the western Bohemian Switzerland not far from its topographical boundary with the Ore Mountains. The region, with its rock pillars up to 30 m high, is one of the major tourist attractions of Bohemian Switzerland. The Tyssaer Wände and their neighbouring Bürschlitzwände (Bürschlické stěny) are protected as a national nature reserve.

Topography and geology

The Tyssaer Wände are located at a height of about 600 m above sea level. They form a line of rock outcrops drawn up in an arc on the westernmost edge of the sandstone beds of the Elbe Sandstone Mountains from the Ore Mountain escarpment on Czech soil. About a kilometre west of them on the outskirts of Tyssa stands the coarse- and medium-grained muscovite-biotite-orthogneiss of the Eastern Ore Mountain region. This also strikes eastwards on the hillside south of the village.

Panoramic view from the so-called Great Wall across the North Bohemian Basin with the Central Bohemian Uplands in the background

The rocks are frequently vertically dissected; in many places the fissures being as deep as the rock pillars are high. Horizontal weathering is found in the upper layers and have created several bizarre shapes, such as the rock called the Steinpilz ("boletus" - a type of toadstool) which is easily accessible.
The Große Tyssaer Steine ("Great Tyssa Rocks") begin near the official entrance by a restaurant. These consist of a northern and southern array of crags along an otherwise compact plateau. The crags to the west running off at an angle to the northwest are known as the Kleine Tyssaer Steine ("Little Tyssa Rocks"). They are more heavily dissected.

The crags of the Tyssaer Wände comprise mainly of medium-grained sandstone of the Lower to Middle Turonian of the Cretaceous. They belong lithostratigraphically to the Weissenberg Formation (Bělohorské souvrství) in the Bohemian Cretaceous System. The nearby area surrounding the Tyssaer Wände to the north and south is covered by diluvial sediments of loam, sand and boulder-containing scree.

In the sandstone are heavy concentrations of ferrous minerals on closely spaced strata, that can be identified from their yellow to red stripes of colour and predominantly horizontal. A striking feature in many places where the lower strata are visible are small and large cavities as well as occasional tunnels with an oval cross-section, whose walls are often covered with calcareous sinter deposits. These are relics of very old solution processes in the sandstone.
In zones of strong weathering, the marked stratification over short distances is clearly visible. Features associated with cross-bedding occur relatively frequently.

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Coordinates: 50°47′16″N 14°1′44″E / 50.78778°N 14.02889°E / 50.78778; 14.02889

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