Borostyán Cave

Borostyán Cave is one of the caves located in Pilisszentkereszt in the Pilis Mountains of the Danube–Ipoly National Park.

Description

Borostyán Cave is situated in the outskirts of Pilisszentkereszt, in a specially protected area. Its entrances are on the É side of the valley that runs from the upper branch of the Vaskapu Valley toward Ny, about 90 m from the branch. To reach the rocks covered with amber draperies that hide Borostyán Cave, one must climb opposite the entrance of Szoplák Valley Cave. Every entrance of Borostýán Cave is narrow and the cave passages are not very spacious. The 16 m long cave formed in Triassic limestone and is not very rich in mineral treasures. The cavity may still be suitable for further research. No permit is required to visit the easily accessible cave. Basic caving equipment is required for entry.

In 1982 the cave was first called Borostyán Cave in the literature.

Research History

The 1967 book *Pilis útikalauz* mentions that in the area of Szoplák Valley Cave, in the Vaskapu Valley, many small cavities hide among the bushes. The 1974 edition of *Pilis útikalauz*, in the list of caves of the Pilis and Visegrád Mountains (pages 19–20), notes that there are Vaskapu Valley caves among the caves of the Pilis and Visegrád Mountains. According to the section describing the caves of the Pilis Mountains, a tourist trail marked with a blue square turns into the Vaskapu Valley beside a forest hut, and after about half a kilometre, a whole series of cavities and small caves is found on the rocky hillside that runs alongside the trail. These are the Vaskapu Valley caves (rock chambers, rock pits), among which Pilis Cave stands out for its size, dripstones, and interesting shapes.

In the 1982 report of the Labor MIM/EKB Esztergomi Karst and Cave Explorers it is stated that the group discovered the Borostyán Cave in the Vaskapu Valley of the Pilis Mountains on November 21, 1982. The manuscript contains a map sketch of the Vaskapu Valley prepared by László Mátéfi (Appendix 1). This site plan shows the geographic location of the Borostyán Cave. The map sketch marks the east direction. Appendix 3 is the floor plan map of the Borostyán Cave, prepared by László Mátéfi. The floor plan map marks the east direction. The 1982 MKBT Report mentions that the Labor MIM/EKB Esztergomi Karst and Cave Explorers carried out exploratory research in 1982 in the Borostyán Cave in the Pilis Mountains.

The 1983 MKBT Programme Book states that the Labor MIM Esztergomi Karst and Cave Explorers on November 21, 1982 found a cavity measuring 0.6 × 1 × 1.5 m in the Vaskapu Valley (Pest County, Pilis Mountains). The filled bottom level of this cavity was lowered by 1 m, thereby revealing a passage that runs in four different directions. The group members gave the name Borostyán Cave to the still small, unexplored, hydrothermal cavity. The January 14, 1983 issue of Magyar Ifjúság mentions that the group called Esztergomi Karst and Cave Explorers discovered the Borostyán Cave located next to the Jóreménység Cave.

The 1991 guidebook repeats the section from the 1974 guidebook that describes the Vaskapu Valley caves, with the difference that, besides the forest hut, the red-marked tourist trail enters the Vaskapu Valley. The 1996 cave day tour guide mentions that among the Vaskapu Valley caves, stone chambers and rock pits, the Pilis Cave stands out both for its size, its interesting shapes, and its dripstones.

In 1997 József Regős and Sándor Kraus surveyed the cave, and then in 1997, using the survey, they prepared the floor plan map of the Borostyán Cave (cave cadastral area 4840) and an 8‑cross‑section map. The floor plan map shows the location of the 8 cross‑sections in the cave. The maps present the cave at a scale of 1:50. The map sheet marks the East‑West direction. In May 1997 Sándor Kraus drew a site plan showing the geographic location of the cavities in the area of the Pilis Cave. The plan shows the geographic location of the cave marked with the name Borostyán. In Sándor Kraus’s 1997 report it is readable that a map of the Borostyán Cave was known before 1997, but a new map of the cave was produced in 1997. It is possible that the cave collapsed. The 1997 site plan was included in the report.

In the 2017 report of the Saint Ozseb Cave Exploration Association it is mentioned that in January 2016 the group noticed warm air emanating from the Honeycomb Cave. From the road running through the valley one could also see the spray hitting the wall above the cave entrance. At the place where the warm air emerged, in the left branch of the left-hand hole, neither the demolition work was clear nor easy. However, work carried out in the other direction (right branch of the left-hand hole) resulted in rapid success. Here, after widening the stalactite, it was possible to crawl into a small chamber walkable by a person, which after removal of the loose, humus‑filled, horrendous fill became comfortable, allowing several people to work in it at the same time. The passage can be broken both forward (toward the mountain) and outward (toward the surface). Forward the group members advanced about 5–6 m, where the stalactite also narrowed and branched in several directions. Some of these are undeveloped stalactite passages with walls chewed and greased by a fox or other animal, but they also continue downward (though they had not yet been examined in detail). It is possible that it would be better to widen further down at the widest part of the chamber, because everything there is interconnected anyway. If there is a continuation further down, it will probably be reached there sooner than by forcefully widening the stalactite passages traversable by a fox. For now this is the main direction of breakthrough in this cave.