Karstic Caves - Baroque Masterpieces of Subterranean Water

Chemical dissolution caused by naturally acidic waters has transformed layers of permeable limestone into an intriguing, subterranean karstic worlds of horizontal caves and vertical abysses. To date over 6,500 such caves have been explored in Slovenia and there are probably as many which are, as yet, unexplored. A complex of subterranean rivers with a dense network of tunnels, labyrinths and huge spaelean halls, most of which are adorned by stalactites and stalagmites and other wondrous forms of sinter and subterranean karstic ornamentation have, over hundreds of thousands of years, steadily been created beneath the land's surface.

Slovenia's most renowned and internationally acclaimed subterranean wonder is the enormous Postojna Cave which, over the past two million years, has been carved out by the Pivka river. The total length of this cave's tunnels is 19.5 km, through part of which a miniature railway takes visitors on a tour.

The 5 km of accessible caverns of the Škocjan Cave near the town of Divača, second in popularity only to Postojna, is detailed on the UNESCO list of Worlds Natural and Cultural Heritage, making it unique in that respect for Slovenia.

The Postojna Cave
 

The 19.5 km long cave system near Postojna, which was created over millions of years by the waters of the Pivka river, is the largest in Slovenia. However, this is more than a mere underground river. The calcium carbonate rich waters, which trickle their relentless way downwards, are constantly but imperceptibly precipitating calcareous sinter. Over the millennia this has created a wonderful subterranean world of undiscernibly materializing stalactite and stalagmite formations.

The Škocjan Caves

Located in the southwest of the country and included on the UNESCO List of World Natural Heritage, are the Škocjan Caves, commonly acknowledged as the most magnificent in Slovenia. These caves have been formed by the Reka river, the terrestrial section of which ends at the great Mahorčič Cave below Škocjan village. Škocjan is precious not only for its vast caverns and beautiful calcite sinter formations, but also because of the history of its exploration and its wild and exposed trails.

Abstract from the book "Vode v Sloveniji" / "Waters of Slovenia", text by Dr Dušan Plut, photographs by Matevž Lenarčič, (Nazarje): EPSI, 1995