The Tisá Rocks or Tisá Walls (; ) are a group of rocks in

Tisá Tisá () is a municipality and village in Ústí nad Labem District in the Ústí nad Labem Region of the Czech Republic. It has about 1,000 inhabitants. Etymology The name is derived from the Proto-Slavic word ''tes'' and the Czech word ''tis'', ...

in the

Czech Republic The Czech Republic, also known as Czechia, and historically known as Bohemia, is a landlocked country in Central Europe. The country is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the south ...

. It is located in the western

Elbe Sandstone Mountains The Elbe Sandstone Mountains, also called the Elbe Sandstone Highlands (, ; , ), are a mountain range straddling the border between the state of Saxony in southeastern Germany and the North Bohemian region of the Czech Republic, with about three-q ...

, not far from its topographical boundary with the

Ore Mountains The Ore Mountains (, or ; ) lie along the Czech–German border, separating the historical regions of Bohemia in the Czech Republic and Saxony in Germany. The highest peaks are the Klínovec in the Czech Republic (German: ''Keilberg'') at ab ...

. The region, with its rock pillars up to 30 m high, is one of the major tourist attractions of the region. The Tisá Rocks and the neighbouring Bürschlické Rocks are protected as a nature monument.

Topography and geology

The Tisá Rocks 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

from the Ore Mountain escarpment on Czech soil. About a kilometre west of them on the outskirts of Tisá stands the coarse- and medium-grained

muscovite Muscovite (also known as common mica, isinglass, or potash mica) is a hydrated phyllosilicate mineral of aluminium and potassium with formula KAl2(Al Si3 O10)( F,O H)2, or ( KF)2( Al2O3)3( SiO2)6( H2O). It has a highly perfect basal cleavage y ...

biotite Biotite is a common group of phyllosilicate minerals within the mica group, with the approximate chemical formula . It is primarily a solid-solution series between the iron- endmember annite, and the magnesium-endmember phlogopite; more al ...

orthogneiss Gneiss (pronounced ) is a common and widely distributed type of metamorphic rock. It is formed by high-temperature and high-pressure metamorphic processes acting on formations composed of igneous or sedimentary rocks. This rock is formed under p ...

of the Eastern Ore Mountain region. This also strikes eastwards on the hillside south of the village. 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 edulis" - a type of edible mushroom) which is easily accessible. The "Great Tisá 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 "Little Tisá Rocks". They are more heavily dissected. The crags of the Tisá Rocks comprise mainly of medium-grained

sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

of the Lower to Middle

Turonian The Turonian is, in the International Commission on Stratigraphy, ICS' geologic timescale, the second age (geology), age in the Late Cretaceous epoch (geology), Epoch, or a stage (stratigraphy), stage in the Upper Cretaceous series (stratigraphy), ...

of the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ...

. They belong lithostratigraphically to the Weissenberg Formation (''Bělohorské souvrství'') in the Bohemian Cretaceous System. The nearby area surrounding the Tisá Rocks to the north and south is covered by diluvial sediments of

loam Loam (in geology and soil science) is soil composed mostly of sand (particle size > ), silt (particle size > ), and a smaller amount of clay (particle size < ). By weight, its mineral composition is about 40–40–20% concentration of sand–si ...

sand Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is usually defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural ...

and boulder-containing

scree Scree is a collection of broken rock fragments at the base of a cliff or other steep rocky mass that has accumulated through periodic rockfall. Landforms associated with these materials are often called talus deposits. The term ''scree'' is ap ...

. 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 Calcareous sinter is a freshwater calcium carbonate deposit, also known as calc-sinter. Deposits are characterised by low porosity and well-developed lamination, often forming crusts or sedimentary rock layers. Calcareous sinter should not be conf ...

deposits. These are relics of very old solution processes in the sandstone. In zones of strong

weathering Weathering is the deterioration of rocks, soils and minerals (as well as wood and artificial materials) through contact with water, atmospheric gases, sunlight, and biological organisms. It occurs '' in situ'' (on-site, with little or no move ...

, the marked stratification over short distances is clearly visible. Features associated with

cross-bedding In geology, cross-bedding, also known as cross-stratification, is layering within a stratum and at an angle to the main bedding plane. The sedimentary structures which result are roughly horizontal units composed of inclined layers. The origina ...

occur relatively frequently.

Gallery

Tyssaer waende, south front, view of tyssa.jpg, South flank of the Tisá Rocks falling steeply into the

Most Basin The Most Basin (also known as North Bohemian Basin; , ) is a structural basin and geomorphological mesoregion of the Czech Republic. It is named after the city of Most. It forms the southwestern and central parts of the Ústí nad Labem Region. ...

Tyssaer waende, sturzblöcke.jpg, Fallen boulders in the Great Tisá Rocks Tyssaer waende, tunnel.jpg, Weathered shapes in a tunnel Januskopf.jpg, The "Head of Janus" Doggenturm-Tisa-03.jpg, Pinnacle of the Doga Tower Doggenturm-Tisa-01.jpg, Pinnacle of the Doga Tower

Panorama

Sources

* Albrecht Kittler: ''Kletterführer Böhmische Schweiz - Raiza und Tyssaer Wände.'' Verlag Kittler, Dresden 2007 * J. Valečka (Red.): ''Geologická mapa ČR, List 02-23 Děčín.'' 1:50,000. Prague (ČGU) 1992, Signaturen 6, 7, 41, 43 * Radim Kettner: ''Allgemeine Geologie. Bd. 2''. Berlin (

Deutscher Verlag der Wissenschaften (DVW) (English: ''German Publisher of Sciences'') was a scientific publishing house in the former German Democratic Republic (GDR/). Situated in Berlin, DVW was founded as (VEB) on 1 January 1954 as the successor of the main department of "un ...

), 1959, p. 293

External links

Tisá
{{DEFAULTSORT:Tisa Rocks Děčín District Elbe Sandstone Mountains Climbing areas of the Czech Republic Geography of the Czech Republic Rock formations of the Czech Republic