Korallos Cave

Korallos Cave is one of the caves located in the Buda Hills of the Danube–Ipoly National Park, in District II of Budapest. It is the longest cave of the French Mine.

Description

In the upper third of Szépvölgyi Road, in front of the southern part of the French Mine north of Erdei Street, its entrance is 10–12 m from the wall section and 4 m higher than the floor level of the mine yard. It is situated on a coral limestone slab that emerges 50 m east‑north from the Látó Hill Cave.

A sloping bedding‑plane fissure cave. It formed in Eocene Szépvölgyi limestone, in which some fossilized organisms (shells) can be observed in places. Pea‑sized stone surfaces have developed scattered on the limestone. Its formation is determined by a tilted (45°) bedding‑plane preformation, probably further enlarged by warm‑water corrosion. Its floor consists of stone rubble and grayish fine‑grained clayey silt.

In 1987 the cave was first called Korallos Cave in the literature.

Research History

It was one of the research sites of the 1987 MKBT research camp and was excavated then. The site map of the French Mine caves, which appeared in the 1987 report *Karst and Cave*, was drawn by Márton Juhász (Cave Institute). The map marks the location of Korallos Cave. From the map it can be determined that among the stone‑mine caves this cave is situated farthest west. The report states that the cave’s exploration began at the start of the camp with the opening of a 1 m deep filled crack. At the end of the camp the enthusiastic excavation team abandoned the exploration in a draughty chamber 18 m long and 8.3 m deep. The journal published the cave’s plan map, extended longitudinal section map and cross‑section map. The maps were edited by Márton Juhász (Cave Institute). The plan map shows the location of the cross‑section within the cave. On the map sheet, the east‑north direction is marked for use with the plan map.

In the 1987 MKBT Program Booklet announcement that saw the light of day, it is written that the Korallos Cave was one of the main hopes and results of the 1987 central research camp. At the end of the cave, which was unfolded to about 20 m in length during the camp, one can see further and there is a very strong draft at the end point. The publication shows the site plan of the French Mine caves, prepared by Márton Juhász (Cave Institute). The location of the Korallos Cave is marked on the site plan.

According to the study published in the 1995 Geological Gazette and written by Szabolcs Leél-Őssy, there are specifically barren, almost mineral‑free caves on and around Rózsadomb, e.g. the Korallos Cave. The Korallos Cave, which was opened during the 1987 research camp in the French Mine next to the inclined limestone layers of Szépvölgy, is a roughly 10 m deep flat fissure. At the end of the cave a very strong airflow emerges, cooling the air in the small cave chamber to about 6 °C.

It received its strange name because of ancient relics in the enclosing rock. It is a promising research point together with the Látó‑hegy Cave. Especially for the old caves, there is considerable uncertainty in some places, mainly regarding the names, but sometimes also concerning the number of caves. This is especially true in the quarries, where many small caves occur, for example in the French Mine. The study was accompanied by a site plan of the caves of Rózsadomb and its surroundings, on which the cave’s location is marked.

The Szabó József Cave Research Department, from 17 May 2011, from the receipt of the research permit, carried out exploratory work in the cave 3–4 times per month, during which muddy and debris-filled sediment was removed from the cave, but the department members did not succeed in reaching a free passage section. The members' goal was to connect the cave with the Pál-völgyi cave system.

The department members in 2012 carried out exploratory work in the cave 3–4 times per month, during which muddy and debris-filled sediment was removed from the cave, but they did not succeed in reaching a free passage section. The members' goal was to connect the cave with the Pál-völgyi cave system. The department members in 2013 carried out exploratory work in the cave once per month, during which muddy and debris-filled sediment was removed from the cave, but they did not succeed in reaching a free passage section. The members' goal was to connect the cave with the Pál-völgyi cave system.