Pénzes-Csontos Cave

The Pénzes-Csontos Cave is one of the caves located in the Pilis Mountains within the Danube–Ipoly National Park, situated in Oszoly. It was formed by connecting two caves, the Pénzes Cave and the Csontos Cave. The two caves are also presented in tourist guidebooks.

Description

The entrance of the Pénzes Cave is in the second large rock group on the east side of the Óra rock located in Oszoly. The passage system was probably formed under phreatic conditions in Upper Triassic Dachstein limestone, as indicated by the solution forms. Apart from a sketch description of the cave and a map of part of it, only climate measurement data are available. The documentation needs to be supplemented as soon as possible.

The Csontos Cave opens 3 m away from the Pénzes Cave, 2 m lower. It formed in Upper Triassic Dachstein limestone and is 6 m long. Recent bone remains were found in its fill. Apart from a sketch description and a map of the cave, only climate data are available. The Pénzes Cave and the Csontos Cave are connected passagewise, forming a single system.

In the literature the cave also appears under the names Csontos Cave (Dely, Mezei 1974), Csontos cave (Kordos 1970), O.IV (Kordos 1970), cave E 1 on the east side of Óra rock (Kordos 1970), Pénzes Cave (Dely, Mezei 1974) and Pénzes cave (Kordos 1970). Csontos Cave was also the name of the Cserepes Cave on Csúcs Hill in Csobánka.

Research history

In the book Pilis guidebook, which appeared in 1967, it was reported that on the southern side facing Oszoly Csobánka, among the forest‑surrounded limestone rocks, there are several insignificant cavities. According to a notice published in the 1969 Karst and Cave Research Bulletin, in August 1969 the Speleology Cave Research Group placed fixed points in the Oszoly and the Oszoly‑side’s eight smaller‑larger cavities during a camp organized in Kevélyek. In 1969 László Kordos and Erzsébet Wehovszky surveyed the Pénzes Cave with fixed points and a mining compass. Based on the survey, László Kordos drew a plan map and an expanded longitudinal section map, both at a scale of 1:100. The survey measured the cave to be 16 m long and 4 m deep.

In 1969, Erzsébet Wehovszky and László Nagy surveyed the Csontos Cave with lost points and a mining compass. Based on the survey, Erzsébet Wehovszky edited, László Kordos drew a floor plan map with two cross‑sections and an extended longitudinal section map, which were made at a scale of 1:100. According to the survey, the cave is 6.5 m long and 3 m deep. On 22 February 1970, 22 March 1970 and 26 April 1970 László Kordos and Péter Welker examined the climate of the Pénzes Cave with an Assmann aspirational psychrometer. On 22 March 1970 and 26 April 1970 László Kordos examined the climate of the Csontos Cave with an Assmann aspirational psychrometer. On 22 March 1970 László Kordos analyzed the water of the Pénzes Cave.

The Speleology Cave Exploration Group writes in its 1970 report that the Pénzes Cave (O.IV, cave number E 1 located east of the Óra wall) opens in the second large rock group east of the Oszoly Óra wall (towards Margitliget). The cave has two entrances. Entrance number 1 is situated among dense bushes, from which narrow fissures lead in three directions. One of these leads to a dome chamber and then to the surface, like entrance number 2, which is about 2 m below entrance number 1. The cave was formed in upper Triassic, white, compact Dachstein limestone. At entrance number 1 there is a rubble fill, at entrance number 2 a humus‑rich fill. It is probably of karst origin. During snow melt strong dripping is observable, otherwise only sparkling water is present. No equipment is needed to explore the cave. In 1969 István Szenthe mentioned the cave, and later in 1969 the Speleology Cave Exploration Group examined and surveyed it.

The Csontos Cave opens about 3 m east of the Pénzes Cave. It consists of a single downward‑going, tube‑shaped, narrowing passage. The cave’s upper part formed in Upper Triassic, white, filled, thick‑bedded Dachstein limestone. Its floor is filled with humus, and it contains many recent bones. It is probably of karst origin. The cave is completely dry. It is recommended to wear work clothing and use a lamp when entering the cave. In 1969–1970 members of the Speleology Cave Exploration Group examined the cave. The report’s annex includes the two caves’ maps made in 1969.

The book *Pilis Guidebook*, which appeared in 1974, mentions in the list of caves of the Pilis Mountains and the Visegrád Mountains (pages 19–20) that among the caves of the Pilis and Visegrád Mountains are the Oszoly caves and the Csontos Cave. According to the section describing the Pilis Mountains caves, there are about a dozen small caves among the Oszoly rocks rising above Csobánka. These were mapped and regularly explored by the Speleology Cave Exploration Group. Most of these small caves are not very spectacular, but they should be mentioned because some of them provide excellent bivouac possibilities in the Oszoly rock walls regularly visited by tourists, especially rock climbers, and in their vicinity. In the second large rock group rising east from Óra‑wall, among dense bushes, the two entrances of the Pénzes Cave open. The cave consists of narrow fissures and a dome‑shaped chamber. Formed in Dachstein limestone, the 16 m long cavity is certainly of karst origin. The Csontos Cave, 6.5 m long, tube‑shaped, downward‑leaning cavity, is located 3 m east of the Pénzes Cave. About 10 m lower than the Csontos Cave is the entrance of the Denevéres Cave.