This exceptional system of limestone caves comprises collapsed dolines, some 6 km of underground passages with a total depth of more than 200 m, many waterfalls and one of the largest known underground chambers. The site, located in the Kras region (literally meaning Karst), is one of the most famous in the world for the study of karstic phenomena.
The Škocjan Caves lie in the north-east section of Kraski Landscape Park. The protected area extends over 200 ha and includes four deep and picturesque chasms, Sokolak in the south, Globocak in the west, Sapen dol and Lisicina in the north. They are components of the cave system and are alike floristically. The site also includes the Mahorcic cave which has several underground lakes and five cascades.
The system of subterranean passages, fashioned by the Reka River, constitutes a dramatic example of large-scale karst drainage. An underground system of passages runs from the Reka's source to Timavo on the Gulf of Trieste in Italy. In places the surfaces of the galleries at several levels have collapsed and give the appearance of deep chasms. The river enters the Škocjan grotto in an underground passage 350 m long, reappearing in the bottom of a 150 m deep and 300 m long chasm, before disappearing into a passage 2 km long. There are five galleries and a canal. A gallery of stalactites and stalagmites leads to the surface. In total there are 25 cascades along the river.
Archeological excavations have revealed that the site has been occupied for more than 10,000 years. Archaeological finds point to continuous settlement from the middle Stone Age to the Iron Age, when a fort was constructed where Škocjan stands today. The Romans erected another fortification in the same place, and during the Middle Ages a fortified rural settlement was established. Documentary references exist since the time of Posidinuis (135-50 BC). It has frequently been written about, with important descriptive works appearing in 1599 and 1689.
A mixture of habitats is represented corresponding to the floras of Central Europe, the Mediterranean, Submediterranean, Ilyrian and Alpine, all of which are present side by side in the Great Valley. The rare endemicCampanula justiniana grows here at its type locality.
The system of grottos is rich in speleofauna. The underground galleries hold five species of wintering bat in large numbers.
Ever since the first scientific studies were carried out in the 19th century, the grotto system has been considered important karst phenomena in Europe and all organizations responsible for it have maintained it intact. The caves were first explored by Svetina in 1839, who descended 100 m into the Reka. Speleological research began in 1851 (and continues to date), research on the water system in 1893 and in 1894 the famous speleologist Martel published the work Les abimes .
The total population of 400 is present in three villages (Škocjan pri Divaci, Matavan and Betanja) within this area.