Stretching along Hungary's northeastern and Slovakia's southeastern border, the contiguous cavern system of the Aggtelek and Slovak Karst, which has unmatched natural and historio-cultural value, was placed on the UNESCO World Heritage List in 1995 on the basis of a joint proposal from both countries. The extraordinary variety, complexity and relative integrity of the natural sub-surface formations were the major factors that convinced the World Heritage Committee. (Incidentally, at the present there are a total of four subterranean cavern systems that have been placed on the List as natural sites; the majority of caves have been inscribed as part of the world heritage as historio-cultural sites - due to fossils of prehistoric man, wall paintings and religious monuments).
Currently there are 712 known caves of various forms within the geographically contiguous unit made by the Aggtelek and Slovak Karst, 273 of these opening onto Hungarian territory. The caves, which were shaped two million years ago out of the approximately 220-240 million-year-old Middle Triassic period limestone, are diverse from the point of view of their size, forms and ecological conditions. The majority of them were formed by the dissolving and erosive effects of water coming from sinkholes on the edge of the limestone area that formed subterranean streams reaching far underground. In addition to this process, we also find vertical pit-caves formed by percolating ground water dissolving the stone, as well as caves formed by warm waters spouting up from below. In addition to stalactites and stalagmites, columns, drains and other dripstone formations, peastone and sheets of calcite adorn the caves.
The most famous cavern of the Aggtelek and Slovak Karst is the Baradla-Domica cave system, whose total length, including branches that have been explored so far, is 25 kilometers -making it Hungary's and the temperate zone's longest cave (the Domica cavern is the 5.6 km section lying in Slovakia). The other notable caverns of the karst region include: the Földváry and Rákóczi Caves on the Esztramos; the Béke Cave, which has medicinal value for those suffering from respiratory disorders; the Vescsmbükk Chasm, which is Hungary's second deepest cave; and the Vass Imre Cavern, which has great hydrological significance.
The Baradla Cavern is mentioned for the first time in 1549, in writings issued in Basel by G. Wernher, and later it is noted in Mátyás Bél's study published in 1742 in Vienna. However, the first detailed description of it appeared only in 1781, in the German-language Ungarisches Magazin from Vienna. In 1794 József Sartory prepared the first measured drawings of it (these drawings are the world's first cave map prepared by an engineer), and János Farkas wrote its first exhaustive description. The first detailed description published with a map is from 1807, thanks to Keresztély Raisz.
The protected natural preserve of the Aggtelek National Park covers a total of 20,170 hectares. It is the first among Hungary's national parks to be created primarily for the preservation of inanimate natural geological features - the surface formations and caverns stretching underground - and only secondarily for the natural living environment there. But, besides its geological importance, the area's biological, palaeontological and archeological value is also significant.
Countless remains found during the course of archeological explorations in the area attest to the fact that prehistoric man already knew of some of the caves, and they were even used as dwellings. The overwhelming majority of the finds come from the Neolithic period, or 6,000 to 7,000 years ago. These include personal implements made from stone or animal bones, and also linear pattern earthen vessels belonging to the Bükk culture. Numerous relics have been found from the early Iron Age as well, though (gold jewelry and battle gear).
The caverns of the Aggtelek and Slovak Karst form a unique ecosystem. The protected subterranean environment provides a home for over 500 cave-dwelling animals. Several species are endemic, or in other words exist only here or were first described here. 21 of the 28 European bat species were registered here, two of which are endangered. Several rare and protected species of fish are also found in the aquatic life that populates the springs and subterranean waters that flow through the system of caverns. The humid environment is also an ideal habitat for amphibians such as the fire salamander.
As a result of all of this Aggtelek and its area contains unique sights for visitors, both above the surface as well as underground. In addition, concerts of serious music are held in the outstanding acoustics of the Baradla Cavern's exceptional auditorium, providing unparalleled enjoyment.