Udvar Rock

Udvar Rock is one of Hungary's highly protected caves. It is located in the Bükki National Park. It is the country's only fissure block. The cave chamber of this collapsed-top water sink is a spectacular natural phenomenon.

Description

It is on the Little Plateau of the Bükk Plateau. At the confluence of a water sink stream coming from the north and a south‑east stream, it is located next to the tourist trail leading to Örvény Stone. Near the sink's gate, four to five large passages met below the surface, whose water carved and dissolved a large chamber in the Triassic limestone. The ceiling of this surface‑near cave chamber collapsed, creating Udvar Rock.

Its gate is 3–3.5 m wide and 1.5–2 m high. The fissure block has vertical walls, a diameter of 18–22 m and a depth of 18 m. Stone blocks hinder its passage. Near the gate, short cavities open at a height of two to three meters. Above the sink passage at the southeastern base of Udvar Rock a 12‑meter‑long arch opens onto the unrocked edge. Above the arch many small cavities and short passages open in the limestone wall. That it was once a cave is evidenced by these stalactite‑filled cave remnants and the fallen rock gate.

Because its width and depth are significant for the rock sinkhole, its temperature and humidity are distinctive, as is the relationship of its snow cover and vegetation. In summer, temperatures at its bottom can often be 10–14 °C lower than the surface temperature. Its air is more humid than the vapor‑rich air of the surrounding forests. Therefore it is rich in mosses, lichens, ferns, mold fungi and tube fungi. The liverworts and leafy mosses here are larger than usual. Since it functions as a snowdrift, after snowy winters, for example after the winter of 1998–1999, vegetation at its bottom was almost completely destroyed under a one‑ to two‑meter‑thick snow layer that remained for months.

The cave also occurs in literature under the names Dante Hell (Schőnviszky 1937), Dante Hell (Bertalan 1976), Dante‑Hell (Bertalan, Schőnviszky 1973–1974), Rock‑gate Water‑drain (Bertalan 1976), Rock‑gate‑water‑drain (Hevesi 1977), Udvar‑stone (Kordos 1975), Udvarkő (Boros 1935), Udvarkő‑cave (Lénárt 1976), Udvarkői‑cave (Szeghalmy 1940), Udvar‑stone‑cave (Bertalan, Schőnviszky 1973–1974), Udvarkői cave (Schőnviszky 1937), Udvarkői‑cave ruin (Szeghalmy 1940), Udvarkői‑ruin‑cave (Lénárt 1975), Udvarkői‑chasm‑valley (Lénárt 1979), Udvarkői chasm‑sinkhole (Jakucs, Kessler 1962), Udvar‑stone‑chasm‑sinkhole (Lénárt 1979), Udvarkői‑water‑drain‑cave (Várszegi, Kositzki 1964) and Udvarkői water‑drain cave (Várszegi, Kositzki 1964).

Research History

The cave was first mentioned in the 1932 Bükk travel guide. According to the book titled Felvidék published in 1940, it is located two and a half hours from Diósgyőr, near the Kaszásréti spring, and is a very interesting cave ruin often visited by tourists, of which only a huge rock gate and a few side chambers remain. The rest was destroyed by the destructive action of water. Its crumbling walls are rich in picturesque rock formations, showing at places a wild and frightening rock landscape, which is why tourists rightly named it Dante Hell. Not far from the cave is the Csókási cave.

In 1964 the Department of Nature Hiking and Karst Research of the Miskolc Miners Sports Club carried out clearing work in it and drew conclusions about the snow‑covered Udvar-kő. In 1974 the biologists of the Bük Nature Conservation Camp studied the vegetation of the Udvarkő fissure chamber and the birds of its environment. In 1975 members of the Cave Research Group of the Nyíregyháza Teacher Training College carried out microclimate measurements in it. In that year the MEAFC Marcel Loubens Cave Research Sub‑group determined that it is connected with the Kő-lyuk cave group, namely the Kő-lyuk, the Kő-lyuk 3., and the János János János János János János Ján? (Note: original text contains "Hillebrand Jenő-barlanggal").

The Nyíregyháza College Cave Research Group in 1976 studied its climate, temperature, humidity and air movement, as well as conducted external air temperature measurements and prepared a plan map of the cave. In 1976 the Udvarkő located in the 5300 (Bükk) cave cartography area became a cave of national significance. In the Hungarian speleology bibliography compiled by Károly Bertalan and László Schőnviszky, published in 1976, the cave index mentions the cave in the Bükk Mountains at Varbó under the name Udvar-kői-barlang with the variant name Dante-pokla. The cave index lists three literary works that deal with the cave.

In the manuscript titled *Hungary's Cave Atlas*, completed in 1976, it is written that the Udvar Stone located in the Bükk Mountains at Varbó, also known as Dante Pokla and Sziklakapus water source, is situated on the right side of the red tourist trail from Kászás to Csókás at an altitude of 425 m a.s.l. Its entrance is a rock gate. The cave is 25 m long and 20 m deep. It is a collapsed cavern. It has tourist utilization. It is a special geomorphological form and a landscape-wise special owl habitat. Conducting demolition and exploration in it is dangerous due to the terrain. The part of the manuscript concerning the cave was written based on six literary works. After correcting the names of the caves listed in the nationwide list of caves compiled in 1976, it appears on the nationwide list of caves compiled on May 30 1977 as the cave named Udvar‑kő located in the Bü̈kk Mountains at Varbó.