Dobšinsk ice cave

History

The opening to the cave under the name "ice hole" has been known for a long time. However, only E. Ruffíny, accompanied by G. Lang, A. Megu and F. Fehér, descended underground in 1870. Thanks to the town of Dobšiná, the cave was made accessible in 1871. Experiments with its electric lighting began in 1881. Proper electric lighting was introduced in 1887. The Dobšinsk ice cave is among the first electrically lit caves in the world. Right from its discovery, it attracted a lot of attention from experts and the general public, and was visited by many important personalities of the time - PO Hviezdoslav, SH Vajanský and others. In 1890, a concert was held in the Great Hall in honor of Karol Ľudovít Habsburg. It was also known for summer skating, which was first held in 1893. In 1947, J. Mišelnický discovered the Vapor Hall, J. Ogurčák the Northern Corridor, and L. Šimkovič the White Hall. In the years 1953-1954, a general repair of the tour route, electric lighting and protective measures were carried out after the discovery of non-iced parts. Currently, 475 m are accessible.

The Dobšinská ice cave is part of the Stratenská cave system. It was formed in Mesozoic Middle Triassic light Steinalm and Wetterstein limestones of the Straten nappe along tectonic faults and interlayer surfaces. It reaches a length of 1491 m and a vertical span of 75 m.

The main part of the cave is a huge cavity descending from the surface opening to a depth of 70 m. It was created by breaking through the rock floors between the corridors created by the submersible Hnilca paleoflow in several development levels. Currently, it is mostly filled with ice, reaching up to the ceiling in places and dividing the cave into separate parts (Small and Great Hall, Ruffíny Corridor, Ground Floor). The Collapsed Dome is partially covered with ice, the northwestern edge of which extends below the nearby Duča precipice. The original shapes of the river modeling are remodeled by frost weathering.

The upper, non-glaciated parts of the cave consist of mostly horizontal corridors and halls with typical river-modeled oval shapes and ceiling troughs. In the non-glaciated parts there are also some forms of sinter filling (stalagmites, stalactites, sinter crusts, traces of soft white sinter).

The conditions for glaciation probably arose in the Middle Quaternary after the collapse of the ceilings and the interruption of the corridor between the Dobšinská Ice Cave and the Stratenská Cave. This created a descending bag-like space with stagnation of cold air, which penetrated underground through the upper opening created by the collapse of part of the ceiling (now the entrance to the cave). By freezing the percolating rainwater, the underground space became icy. The beginnings of the creation of the ice fill allegedly go back to the Riss Ice Age (about 300 to 140 thousand years ago), or until the end of the Mindel Ice Age.

Ice fill occurs in the form of floor ice, ice falls, ice stalagmites and pillars. The glaciated area is 9772 m2, the volume of ice is more than 110,100 m3. The largest ice thickness of 26.5 m is in the Great Hall. The layering of the ice is formed depending on the infiltration of rainwater during individual years. At the contact with the bedrock, the ice decreases by melting. The continuous replacement of the ice filling is said to take 1700 to 2000 years. The ice moves slowly from the entrance, the Small and the Great Hall towards the Ground Floor and Ruffín Corridor (2 to 4 cm per year). The Dobšinsk Ice Cave is one of the most important ice caves in the world, which is highlighted by its location outside the Alpine high-mountain area (underground ice is only 920 to 950 m above sea level).

The average annual air temperature in the glaciated Great Hall reaches -0.4 to -1.0 °C (-2.7 to -3.9 °C in February, around +0.2 °C in August). The air temperature in the lower parts of the cave remains below freezing all year round. The relative humidity of the air in glaciated parts is mostly 75 to 90%, sometimes even above 90%. The air temperature in non-iced parts is +0.8 to +3.5 °C, relative humidity 85 to 98%. It is a static-dynamic cave with a different winter and summer air flow regime. In the winter, cold air flows from the surface to the underground, in the summer, the opposite.

The cave represents the most important wintering grounds of the bearded bat (Myotis mystacinus) and Brandt's bat (Myotis brandtii) in Central Europe. Among the 12 species of bats found in the cave, the presence of the coastal bat (Myotis dasycneme) and the ciliated bat (Myotis nattereri), which are among the rarest species of bats in Slovakia, is significant.