Fekete Cave

Fekete Cave is one of the highly protected caves of Hungary. It is located in the Bükki National Park. It is Hungary's eighth deepest and ninth largest cave by vertical extent. It is the fourth deepest and fourth largest cave by vertical extent in the Bükk region after Bányász Cave, István-lápai Cave and Jáspis Cave.

Description

It opens in a rock cleft on the northeastern side of the Great Plateau of the Bükk highlands, at the southern end of the Tekenő Valley, about 60–85 metres from the entrance of the Tekenős‑zsomboly, in a periodically active water sinkhole whose entrance is most often reached by a dry streambed. It can be approached on foot or by off‑road vehicle from the Tekenő Ridge via a dirt road. The cave entrance has a barrel‑shaped concrete roof. At the entrance a commemorative plaque placed for the 30th anniversary of the cave’s exploration can be seen.

After the entrance there is an approximately 12‑metre‑deep, stepped, reinforced‑concrete shaft equipped with built‑in iron ladders. At the bottom of the shaft, in the first narrow section, the cave is sealed with a steel grate. Its passages were formed in anisotropic dark‑gray, black, calcitic dolomite, lower Triassic limestone, upper Permian dark‑gray limestone and Ladinian porphyrite. It is a branching, multilevel, periodically active, typical water‑sinkhole cave formed along tectonic faults. The stepped shaft series is divided by short, steep‑gradient streambed sections, chambers of various sizes and muddy crawling passages.

During the Kolmogorov test a constant‑water source flows into the periodically active water conduit passage. At the upper part of the István Torda branch a permanent water lake with an area of about 3 × 6 metres has formed. In another, already dry lake, the Crystal Lake, there are spherical but crystal‑covered formations below the former water level. The siphon number 1 is often filled with water and then the passages behind it are not passable. At its deepest point a passing siphon, the siphon number 2, blocks the way. In the middle part there is a large labyrinthine sink zone where varied dripstones have formed. The largest chamber is the Hungarian Carlist, which is a roughly 20‑metre‑high and 10‑metre‑wide, narrow‑tapered chamber.

A common large‑scale morphology is the horn, the shaft, the meander and a few spherical chambers can also be encountered in the cave. The small‑scale morphologies are represented by spherical pots, ceiling planes, erosional pots, wave shells, finger‑joint arches and sinuous forms in meandering passages. In the Main branch there are not many dripstone formations, but they occur abundantly in the upper, newly discovered passages. In the cave there are pendant dripstones, straw dripstones, stalactite‑like dripstones, dripstone columns, dripstone flags, dripstone drops, dripstone flows, micro‑terrariums, dripstone basins, cave pearls, crystalline pea stones, typical spherical pea stones, coral‑pea stones and especially in the highest passages helicites, as well as occasional dissolution observed on the dripstones.

Among the bats observed in the cave so far, four species are strictly protected. The water collection area is slightly less than one square kilometre. Periodically there is a 20 metre high waterfall inside it. Flood‑dangerous cave. Suddenly, during heavy rain, the water flowing into the cave, which can be as much as 500 litres per minute, can make almost the whole cave impassable. Visiting is possible only with the permission of the Bükki Nemzeti Park Directorate, using rope‑technical equipment and with good fitness and climbing skills. Since the cave can be traversed only with rope‑technical equipment, few people visit it, therefore most of its formations are intact. The waters that disappear in the cave reappear at the Margit‑forrás.

Hungary's eighth deepest and ninth largest cave by vertical extent. The fourth deepest and fourth largest cave by vertical extent in the Bükk region after the Bányász‑barlang, the István‑lápai‑barlang and the Jáspis‑barlang. On 31 December 1981 it was the country's fifth deepest and the Bükk region's third deepest cave. The seventh longest cave in the Bükk region is the István‑lápai‑barlang, the Bolhási–Jávorkúti‑barlang system, the Hajnóczy‑barlang, the Létrási‑vizesbarlang, the Szivárvány–Sebes‑barlang system and the Szepesi–Láner‑barlang system.

The Torda István branch was named after István Torda, a member of the MAFC Cave Exploration Group, who died at the age of 23 in the Gouffre Berger (a cave in France). In this cave section a memorial plaque also preserves his memory. The part called the Kolmogorov test was named after Andrei Nikolayevich Kolmogorov, the reason for the naming is unknown. The Jean Marais branch was named after Jean Marais because the rope technique borrowed from old French films was used, allowing the ascent of the shaft to be solved only in this way. The room called Magyar Carlista was named after the Torca del Carlista, a cave in Spain, because in this room formations similar to those in the Spanish cave can be observed. The name Fekete Cave was given because of its essentially dark-colored rocks. In the literature the cave also occurs under the names Black Cave (Kordos 1977), Fekete Cave (Kordos 1977), Tekenősi Fekete-barlang (Nyerges 1997), Tekenős-víznyelő (Kordos 1984), Teknős-víznyelő (Dely 1970) and Teknős víznyelő (Kordos 1984).

Research history

In the summer of 1975 Ernő Simon, a member of the Karst Hydrogeology Working Group of the Technical University of Miskolc, discovered the periodic water sink and considered it probable that by making the swallowing point of the water sink passable a large cave could be entered. After three months of clearing the entrance collapse, on 9 November 1975 the cave was entered by the speleologists of the working group. In 1975 the cave was known to a length of about 1000 m. In the 1976 issue of Karst and Cave a schematic cave map sketch of it was published.