In the north-west region of Yugoslavia, in the tiny republic of Slovenia, lies an area known as the Karst, a name given by the ancient Celtic tribes who settled in the rugged limestone foothills of the Dinaric Alps. We are all familiar with the term Karst today, for it has come to mean any area of deeply eroded limestone or dolomite. The limestone here is of Upper Cretaceous age, and during the Miocene it became folded and now rests unconformly upon impermeable sandstones and marls of Eocene age. The area around the little village of Postojna, lying at a height of 1700 feet above sea level, forms part of the Pivka basin, and the surrounding limestone hills, whose-peaks rise to heights of 6000 feet, are riddled with caves - so far 5000 have been discovered, and of these, 11 are opened to the public as tourist caves. Grandest of them all is the Postojna Cave, its chambers extending some 14 miles into the hills above the tiny village from which it takes its name.

Between one and 2 million years ago, glacial melt waters enriched the Nanosica and Pivka rivers to begin the task of cutting into the limestone rocks, gradually forming a vast network of caverns. Archaeological evidence suggests that the Postojna Caves were inhabited during the end of the last glaciation by Paleolithic Man, and there is evidence in the so called Gallery of Old Signatures that modern man first visited the caves as early as the 13th century. The caves were officially opened to the public in 1819, and today Postojna rates as Yugoslavia’s number 1 tourist attraction, with 800,000 visitors annually. In the summer months the average daily figure can top 10,000.

The tourist route extends for 3 miles, the first mile and a half of which is by electric train. What one sees from the train as it passes through narrow passageways and huge chambers is a remarkable display of stalagmites and stalactites, but this is only a hint of what is to come. As the train pulls up in a huge cavern beside a massive section of rock known as the Great Mountain, the tourist is confronted by a stunning spectacle of stalagmites and stalactites. Then the tour on foot begins, a journey into a fantasia of staggering formations, each fashioned into its own unique shape; glistening white pillars, curtains tinged red and orange and brown, “frozen waterfalls” of calcite, huge forests of stalagmites and pointed stalactites. Experts have been able to ascertain that the position of the Postojna Caves, with their covering of coniferous forest, is ideal for the formation of such features, because here the soil retains moisture longest, and provides a steady supply of water to trickle through the limestone rocks. The soil beneath the forest area is saturated with calcium carbonate, which the percolating water will pick up and deposit in the caves in the form of calcite. The colour of the formations is due to impurities - 99% is pure calcite, the remainder is clay or ferric dioxide content. When water trickles along an overhang, a curtain is formed. When a stalactite and stalagmite meet and join together, a pillar is formed, and it has been estimated that the most beautiful formations of Postojna have taken 10,000 years to be created.

The mile long tour on foot takes the visitor on a breathtaking journey through a labyrinth of passageways and chambers. It is the sheer size of the caverns which is awe-inspiring - some caverns feet high, with stalactites rising to 100 formations up to 24 feet of spectacular outstanding of which is “Brilliant”, a glistening white pillar which has become the symbol of the Postojna Caves. As the route passes along winding passageways, each new twist and turn reveals another fairy-tale scene. There is the “Magical Garden”, a crystallised forest of weirdly shaped stalagmites, the “Nice Gallery”, its ceiling supported by pillars of golden brown and adorned with countless thousands of pointed stalactites, and the climax of the tour, a visit to the “Gallery of the Brilliant” where the beauty of the Postojna Caves is best exemplified in the white pillar which gives the gallery its name. The tour terminates in a huge chamber known as The Concert Hall, 220 feet long and 120 feet high, where electric trains wait to transport the tourist back to the realities of the 20th century world outside.

My visit to the Postojna Caves was for me, like I am sure it was for the other 800,000 who visited Postojna during 1983, an enthralling journey into a strange underground world which will rate among the most memorable journeys of my life. No matter how many beautiful palaces, cathedrals or temples man has created, nothing can match the spectacular wonders of the world which nature herself has fashioned.

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