Segeberger Kalkberg
Encyclopedia
The Kalkberg is a 91-metre-high rock in the center of Bad Segeberg
. The name is a misnomer
as it is not made of limestone
(calcium carbonate), but from gypsum
(calcium sulfate
).
sediments, which were deposited about 250 million years ago by the Zechstein Sea. Smaller disturbances in the more recent epochs of earth history allowed the less dense Zechstein salts to flow together and force their way upwards from a great depth into the younger overlying rocks to a level near that of the present-day surface. Under the Kalkberg is a salt dome
, which rises by one to two millimeters a year. The red cliffs of Heligoland
or the Münsterdorfer Geestinsel are limestone, one of the few formations in Schleswig-Holstein
which was not created by the ice ages. The mining of the salt dome ended in 1860. From the salt dome comes the brine feeding the saltwater bath that give Bad Segeberg its name.
, Lothair of Saxony built a castle on the mountain - then called Alberg. It was destroyed in the Thirty Years War by the Swedes. Today, only a well shaft remains.
In 1913, limestone caves which located in the lower part of the rock were discovered. They are home to bat
s and the only known Segeberger cave beetles (Choleva septentrionis holsatica).
Before the First World War, the Kalkberg was property of the Prussia
n state, which every year made not inconsiderable profits from the gypsum mining. After the discovery of the cave, the Prussian Ministry of Trade and Industry agreed to quarry operation with the provision of long-term protection of the town of Bad Segeberg. Finally, it was purchased in 1922 by the city. The commitment to the preservation of the mountain came only quite late: mining ended in 1931. Over the years, the rock lost about two-thirds of its original mass.
Between 1934-1937, the Reich Labor Service built the Kalkberg Stadium, in the pit created by the gypsum mining. This is an outdoor stage with about 7800 seats and standing room for 12,000. The Karl May festival has bee held here every year since 1952.
Until 11 April 1942, the remains of the Kalkberg and part of the cave was designated a natural monument. The natural monument included only to the open faces and the rock immediately below the cave. Large parts of the cave system were thus legally unprotected.
The Protection Order on 18 September 1995 expanded protection to the cave in its full extent and Little Segeberg Lake (at the foot of the Kalkberg) as a nature reserve. Thus, Kalkberg, cave and Little Segeberg Lake were recorded here for the first time as a geological unit.
. A staircase leads from the "Gipfelweg" (Gypsum Way) from the edge of the 43-meter-deep well shaft of the former castle. Visits to the Kalkberg cave are possible between April and September.
There is also a limestone mountain in the Lower Saxony town of Lüneburg
: the Lüneburger Kalkberg. The underlying salt dome was leached away completely in the Middle Ages.
Bad Segeberg
Bad Segeberg is a German town of 16,000 inhabitants, located in the state of Schleswig-Holstein, capital of the district Segeberg. It is situated approximately northeast of Hamburg, and west of Lübeck.It is famous for its annual Karl-May-Festival...
. The name is a misnomer
Misnomer
A misnomer is a term which suggests an interpretation that is known to be untrue. Such incorrect terms sometimes derive their names because of the form, action, or origin of the subject becoming named popularly or widely referenced—long before their true natures were known.- Sources of misnomers...
as it is not made 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....
(calcium carbonate), but from gypsum
Gypsum
Gypsum is a very soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O. It is found in alabaster, a decorative stone used in Ancient Egypt. It is the second softest mineral on the Mohs Hardness Scale...
(calcium sulfate
Calcium sulfate
Calcium sulfate is a common laboratory and industrial chemical. In the form of γ-anhydrite , it is used as a desiccant. It is also used as a coagulant in products like tofu. In the natural state, unrefined calcium sulfate is a translucent, crystalline white rock...
).
Geology
The gypsum was formed as sulfate evaporiteEvaporite
Evaporite is a name for a water-soluble mineral sediment that result from concentration and crystallization by evaporation from an aqueous solution. There are two types of evaporate deposits, marine which can also be described as ocean deposits, and non-marine which are found in standing bodies of...
sediments, which were deposited about 250 million years ago by the Zechstein Sea. Smaller disturbances in the more recent epochs of earth history allowed the less dense Zechstein salts to flow together and force their way upwards from a great depth into the younger overlying rocks to a level near that of the present-day surface. Under the Kalkberg is a salt dome
Salt dome
A salt dome is a type of structural dome formed when a thick bed of evaporite minerals found at depth intrudes vertically into surrounding rock strata, forming a diapir....
, which rises by one to two millimeters a year. The red cliffs of Heligoland
Heligoland
Heligoland is a small German archipelago in the North Sea.Formerly Danish and British possessions, the islands are located in the Heligoland Bight in the south-eastern corner of the North Sea...
or the Münsterdorfer Geestinsel are limestone, one of the few formations in Schleswig-Holstein
Schleswig-Holstein
Schleswig-Holstein is the northernmost of the sixteen states of Germany, comprising most of the historical duchy of Holstein and the southern part of the former Duchy of Schleswig...
which was not created by the ice ages. The mining of the salt dome ended in 1860. From the salt dome comes the brine feeding the saltwater bath that give Bad Segeberg its name.
History
Originally, the Kalkberg was about 110 m high. After centuries of mining of the gypsum, it stands only 91 meters today. In the Middle AgesMiddle Ages
The Middle Ages is a periodization of European history from the 5th century to the 15th century. The Middle Ages follows the fall of the Western Roman Empire in 476 and precedes the Early Modern Era. It is the middle period of a three-period division of Western history: Classic, Medieval and Modern...
, Lothair of Saxony built a castle on the mountain - then called Alberg. It was destroyed in the Thirty Years War by the Swedes. Today, only a well shaft remains.
In 1913, limestone caves which located in the lower part of the rock were discovered. They are home to 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 and the only known Segeberger cave beetles (Choleva septentrionis holsatica).
Before the First World War, the Kalkberg was property of the Prussia
Prussia
Prussia was a German kingdom and historic state originating out of the Duchy of Prussia and the Margraviate of Brandenburg. For centuries, the House of Hohenzollern ruled Prussia, successfully expanding its size by way of an unusually well-organized and effective army. Prussia shaped the history...
n state, which every year made not inconsiderable profits from the gypsum mining. After the discovery of the cave, the Prussian Ministry of Trade and Industry agreed to quarry operation with the provision of long-term protection of the town of Bad Segeberg. Finally, it was purchased in 1922 by the city. The commitment to the preservation of the mountain came only quite late: mining ended in 1931. Over the years, the rock lost about two-thirds of its original mass.
Between 1934-1937, the Reich Labor Service built the Kalkberg Stadium, in the pit created by the gypsum mining. This is an outdoor stage with about 7800 seats and standing room for 12,000. The Karl May festival has bee held here every year since 1952.
Until 11 April 1942, the remains of the Kalkberg and part of the cave was designated a natural monument. The natural monument included only to the open faces and the rock immediately below the cave. Large parts of the cave system were thus legally unprotected.
The Protection Order on 18 September 1995 expanded protection to the cave in its full extent and Little Segeberg Lake (at the foot of the Kalkberg) as a nature reserve. Thus, Kalkberg, cave and Little Segeberg Lake were recorded here for the first time as a geological unit.
Tourism
There are paved walk ways up to the summit platform, which is a popular viewing point. The view extends all around well into the hills of Schleswig-Holstein, in good visibility up to the church towers of LübeckLübeck
The Hanseatic City of Lübeck is the second-largest city in Schleswig-Holstein, in northern Germany, and one of the major ports of Germany. It was for several centuries the "capital" of the Hanseatic League and, because of its Brick Gothic architectural heritage, is listed by UNESCO as a World...
. A staircase leads from the "Gipfelweg" (Gypsum Way) from the edge of the 43-meter-deep well shaft of the former castle. Visits to the Kalkberg cave are possible between April and September.
There is also a limestone mountain in the Lower Saxony town of Lüneburg
Lüneburg
Lüneburg is a town in the German state of Lower Saxony. It is located about southeast of fellow Hanseatic city Hamburg. It is part of the Hamburg Metropolitan Region, and one of Hamburg's inner suburbs...
: the Lüneburger Kalkberg. The underlying salt dome was leached away completely in the Middle Ages.