The Škocjan Caves are a unique natural phenomenon, the creation of the Reka River. The Reka River springs from below the Snežnik plateau and flows some fifty-five kilometres on the surface. After reaching the Karst, it dissolves the limestone. In the first part of its course on the limestone, the Reka still flows on the surface, along an around four-kilometre-long gorge that ends with a magnificent wall under which it disappears underground. The Reka River blind valley is the largest in Slovenia. In the distant past, probably in the Early Pleistocene, that is a few hundred thousand years ago, the ceiling of the cave collapsed some 200 metres from the sinks; as a result, the collapse created two valleys - Velika dolina (up to 165 metres deep) and Mala dolina (120 metres), separated by a natural bridge, a remnant of the original cave ceiling.
In 1986, the Škocjan Caves were entered on UNESCO’s list of natural and cultural world heritage sites due to their exceptional significance. International scientific circles have thus acknowledged the importance of the Caves as one of the natural treasures of planet Earth.
Ranking among the most important caves in the world, the Škocjan Caves represent the most significant underground phenomena in both the Karst region and Slovenia.
From time immemorial, people have been attracted to this gorge where the Reka River disappears into the underground as well as into the mysterious cave entrances. The Reka River sinks under a rocky wall on the top of which lies the village of Škocjan, after which the Caves are named.
Archaeological research has shown that people lived in the caves and the surrounding area in prehistoric times – from the Mesolithic, the Neolithic, the Bronze and Iron Ages through Antiquity and the Middle Ages to the present, which is altogether for more than 5,000 years. The finds from this area testify that the Škocjan Caves had not only local but regional importance in prehistoric times. Pioneering research of Karst and karst phenomena began in this area in the 19th century. The international karstological terms "karst" and "doline" originate here.