Angyal-forrási Cave

Angyal-forrási Cave is one of the caves in Hungary that are highly protected. It is located in Tóváros, (Tatár) in the Danube–Ipoly National Park. Archaeological finds have been recovered from it.

Description

The cave located in the Angolkert of Tata. Permission from the Danube–Ipoly National Park Directorate is required for its exploration.

The spring cave is a speleological curiosity because it did not form in karstified rocks but in a gravel conglomerate and in loess. The first descriptions mistakenly reported a cavity formed in limestone. This was due to the fact that the gravel‑stone walls are covered in many places by limestone that precipitated from the water rich in calcium carbonate. The gravel conglomerate that makes up the cave’s host rock is geologically a mixed gravel of Pannonian age. The size of the individual gravels varies within wide limits, the largest being about 20 centimetres, while the lower limit already falls into the sand‑grain size range. The cementing material of the gravels is mostly calcium carbonate, which – perhaps in the period before the cave formed – was precipitated from a calcium‑rich spring system, binding the gravel‑sand matrix.

The amount of binding material varies, generally 15–25%. The rock is very solid, perhaps also thanks to this, the main passage only 2–3 metres thick has not collapsed yet. During the investigation, the many sediments extracted from the talc‑bearing layer have not yet been fully examined, but the results obtained so far have already provided several surprising, interesting novelties. Originally existing beneath the cave surface there is a so‑called cake‑clay about 30–50 centimetres thick. This consists of colloidal particle fractions, rhythmic, high in calcium carbonate, finely layered sediment. Its presence is surprising because, despite the massive quantity and energy of the breaking water flow, presumably turbulent, it indicates slow and calm deposition conditions.

Below this followed gravel layers containing archaeological finds, then a glass‑like layer from which perfectly mirror‑polished tiny pebbles and spherical ash grains can be selected. These are very beautiful, colorful, shiny as gemstones. Their material is most often quartz, which can be completely transparent rock crystal, colored quartz, microcrystalline SiO₂ varieties (carnelian, jasper, chalcedony) etc. From the fine gravel layer a few tiny mirror‑shiny Eocene nummulite shells were also managed to be selected. Their presence is surprising because, according to the known geological cross‑section, the spring conduit could not have penetrated Eocene layers! Perhaps the water picked them up from a more distant rock unit intersected by the karst water path. Another fine sandy layer proved to be extremely rich in magnetite: approximately 1 m³ of this fill contains 10 kilograms of magnetic iron ore (Vajna György 1977).

In 1980 the cave was first called Angyal‑forrási‑barlang in the literature. The cave also appears in the literature under the names Angyalforrás‑barlang (Bertalan 1976), Angyal‑forrás barlangja (Eszterhás 1992), Angyal‑forrás Cave (Takácsné, Eszterhás, Juhász, Kraus 1989), Tatai‑tavasbarlang (Kordos 1984), Tatai tavasbarlang (Bertalan 1976) and Pokol‑forrás.

Research History

In the manuscript titled *Hungary’s Cave Register* completed in 1976 it can be read that the Tatai tavasbarlang, also known as Angyalforrás‑barlang, is located in the Gerecse Mountains, at Tata. It opens from the Angyal‑forrás spout in the Néppark at an altitude of 141 m above sea level. Its entrance is in a concrete shaft. The spring cave is 20 m long and 7 m deep. The part of the manuscript concerning the cave was written based on three literary works. In 1976 the Angyal‑forrás cave of Tatabánya, located in the 4600 (Gerecse Mountains) cave‑cadastral area, became a cave of national significance.

After the correction of cave names in the list of caves of national significance compiled in 1976, the cave located in the Gerecse Mountains, in Tata, appears on the list of caves of national significance compiled on May 30, 1977 under the name Angel‑source Cave. It was published in the 1980 issue of Karst and Cave, first half, that the highlighted Angel‑source Cave is located in the 4600 cave‑cadastral area (Gerecse Mountains, Gete). The cave’s cave‑cadastral number is 4630/46. The MKBT Documentation Committee will place at the site, as with the other highlighted caves, the metal plate bearing the cave‑cadastral number of the cave. The metal plate used for the cave‑cadastral number will be the same as the metal plates of the other highlighted caves. It was made public in the 1981 issue of Karst and Cave, 1–2. half, that the Angel‑source Cave’s cave‑cadastral number is 4630/46 (the cave‑cadastral number had been previously reported).

From July 1, 1982, according to the President of the National Environment and Nature Protection Office’s decree No. 1/1982 (III. 15.) OKTH (sections 1 and 3, and annex 5), the Angel‑source Cave in the Gerecse Mountains is a specially protected cave. The September–October 1982 MKBT Programme Book mentions that the Angel‑source Cave in the Gerecse Mountains is a specially protected cave. In the list, the cave names were presented in the corrected form according to the spelling approved and used by the MKBT.

According to the book *Magyarország barlangjai* published in 1984, the Tata Angyal-forrási Cave's brightly polished chamber resembles a room paved with marble slabs. In the national cave list contained in the publication, among the caves of the Gerecse Mountains, the cave with the cave survey number 4630/46 is listed as Angyal-forrási Cave with the name variant Tatai-tavasbárlang. Related to the list, the geographical location of the cave is shown on a 1:500 000 scale map presenting the geographical positions of the caves of the Dunazug Mountains. Because of its unique character and the beauty of its formations, this cave was also added in 1988 to the list of highly protected caves.