Kostanjevica Cave, Karst cave in Kostanjevica na Krki, Slovenia

Kostanjevica Cave is a natural underground passage near Kostanjevica na Krki that visitors can explore on guided tours. The dark stone walls display stalactites hanging from above and stalagmites rising from the floor, formed over thousands of years by water slowly carving through limestone.

Before 1969 the cave was called Jama nad izvirom Studene or Studena jama. In 1937 rising water tore away rock and opened the present entrance, after which exploration began. Electric lighting was installed in 1971 together with a 300-metre visitor path through the most attractive sections; the cave is about two kilometres long and research continues.

The cave was called Jama nad izvirom Studene, or Studena jama, until 1969, a name tying it to the Studena spring below the Gorjanci slopes. Since 1971 a lit 300-metre route has let visitors walk through the sinter formations; guided tours with commentary last fifty minutes.

The cave has safe paths that are easy to follow for visitors of all ages, with guided tours offered regularly during the day. Wear comfortable shoes and bring a light jacket, as the temperature inside stays steady but cool.

Before 1969 the cave was called Jama nad izvirom Studene or Studena jama. The present entrance only opened in 1937, when rising water tore away rock, and exploration began that year. Electric lighting and a 300-metre visitor path followed in 1971.