From the subterranean wonderland of Postojna Cave to the majestic peaks of the Kamnik-Savinja Alps, Domhnall O’Donoghue explores the many levels of Slovenia — and instantly falls in love with the country Rajhenburg Castle. Photo: Slovenian Tourist Board and Andrej Tarfila I’m among a hundred passengers squeezed onto a stationary, electric locomotive. We sit in silence, ramrod straight, anticipating our expedition into Slovenia’s Postojna Cave, one of the largest of its kind in Europe.

In a rainbow of languages, the guides forbid us from using the flash on our cameras. Understandably so, as bright light encourages the growth of lichens and fungi, which, in turn, damages the limestone and distresses the cave’s unique inhabitants. Not bats, the temperatures here are too cold, but rare blind fish — affectionately known as Baby Dragons — who can survive up to a decade without eating.

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