Atta Cave
Encyclopedia
The Atta Cave or Attendorn Dripstone Cave (Attendorner Tropfsteinhöhle) in Attendorn
is one of the largest and most beautiful dripstone caves in Germany.
The cave was discovered during the quarrying of limestone at the Bigge Valley Limestone Works (Biggetaler Kalkwerk) on 19 July 1907 and was opened up by the owners to tourists that same year. Today the Atta Cave is the most-visited show cave
in Germany, receiving around 350,000 tourists per year, and is an important economic factor for the town.
Amongst its attractions are numerous calc-sinter flowstone
drapes, colourfully tinctured by iron oxide
s. There are also many stalactite
s, stalagmite
s and stalagnates. Several pieces of calcite crystal formations were moved into the public area of the cave in order to be displayed there.
era (about 400 million years ago) when the region of the present-day cave still lay in a bay of the sea. In the layers of limestone
then being laid down, caverns were formed over time by carbonic acid
weathering caused by the rainwater seeping through it as well as mixed corrosion (Mischungskorrosion).
An earthquake several thousand years ago broke several of the speleothem
s. The caves are also inhabited by bat
s that get into the cave through rock crevices in the hilltop.
Other parts of the cave were discovered in 1985 by Elmar Hammerschmidt. The total length of the cave is 6,000 metres but it has not been completely surveyed. For the show cave section there is a roughly 500 m long circular tour. It is reached through a 90 metre long gallery through which visitors are guided. The original entrance is sealed today with a metal door. In one part of the cave, cheese is stored, a water curtain is supposed to help stop the smell spreading too far.
The cave is still in private hands today. It has been criticised for its high entry charges and ban on photography.
Attendorn
Attendorn is a German town in the Olpe district in North Rhine-Westphalia.As of 2008 it had a population of 24, 801.- History :The town’s location was favoured by the good climate in the Attendorn-Elsper Limestone Double Basin , the fruitful soil and favourable transport potential, and was already...
is one of the largest and most beautiful dripstone caves in Germany.
The cave was discovered during the quarrying of limestone at the Bigge Valley Limestone Works (Biggetaler Kalkwerk) on 19 July 1907 and was opened up by the owners to tourists that same year. Today the Atta Cave is the most-visited show cave
Show cave
Show caves — also called tourist caves, public caves, and in the United States, commercial caves — are caves that are managed by a government or commercial organization and made accessible to the general public, usually for an entrance fee...
in Germany, receiving around 350,000 tourists per year, and is an important economic factor for the town.
Amongst its attractions are numerous calc-sinter flowstone
Flowstone
Flowstones are composed of sheetlike deposits of calcite formed where water flows down the walls or along the floors of a cave. They are typically found in "solution", or limestone caves, where they are the most common speleothem. However, they may form in any type of cave where water enters that...
drapes, colourfully tinctured by iron oxide
Iron oxide
Iron oxides are chemical compounds composed of iron and oxygen. All together, there are sixteen known iron oxides and oxyhydroxides.Iron oxides and oxide-hydroxides are widespread in nature, play an important role in many geological and biological processes, and are widely utilized by humans, e.g.,...
s. There are also many stalactite
Stalactite
A stalactite , "to drip", and meaning "that which drips") is a type of speleothem that hangs from the ceiling of limestone caves. It is a type of dripstone...
s, stalagmite
Stalagmite
A stalagmite is a type of speleothem that rises from the floor of a limestone cave due to the dripping of mineralized solutions and the deposition of calcium carbonate. This stalagmite formation occurs only under certain pH conditions within the underground cavern. The corresponding formation on...
s and stalagnates. Several pieces of calcite crystal formations were moved into the public area of the cave in order to be displayed there.
History
The formation of the cave started in the DevonianDevonian
The Devonian is a geologic period and system of the Paleozoic Era spanning from the end of the Silurian Period, about 416.0 ± 2.8 Mya , to the beginning of the Carboniferous Period, about 359.2 ± 2.5 Mya...
era (about 400 million years ago) when the region of the present-day cave still lay in a bay of the sea. In the layers of limestone
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
then being laid down, caverns were formed over time by carbonic acid
Carbonic acid
Carbonic acid is the inorganic compound with the formula H2CO3 . It is also a name sometimes given to solutions of carbon dioxide in water, because such solutions contain small amounts of H2CO3. Carbonic acid forms two kinds of salts, the carbonates and the bicarbonates...
weathering caused by the rainwater seeping through it as well as mixed corrosion (Mischungskorrosion).
An earthquake several thousand years ago broke several of the speleothem
Speleothem
A speleothem , commonly known as a cave formation, is a secondary mineral deposit formed in a cave. Speleothems are typically formed in limestone or dolostone solutional caves.-Origin and composition:...
s. The caves are also inhabited by bat
Bat
Bats are mammals of the order Chiroptera "hand" and pteron "wing") whose forelimbs form webbed wings, making them the only mammals naturally capable of true and sustained flight. By contrast, other mammals said to fly, such as flying squirrels, gliding possums, and colugos, glide rather than fly,...
s that get into the cave through rock crevices in the hilltop.
Other parts of the cave were discovered in 1985 by Elmar Hammerschmidt. The total length of the cave is 6,000 metres but it has not been completely surveyed. For the show cave section there is a roughly 500 m long circular tour. It is reached through a 90 metre long gallery through which visitors are guided. The original entrance is sealed today with a metal door. In one part of the cave, cheese is stored, a water curtain is supposed to help stop the smell spreading too far.
The cave is still in private hands today. It has been criticised for its high entry charges and ban on photography.
Sources
- Rainer Ahrweiler, Elmar Hammerschmidt: Attendorner Tropfsteinhöhle. In: Die Höhlen der Attendorn-Elsper Doppelmulde, Karst und Höhle 1991/92, VdHK München, ISSN 0342-2062, pages 25-36