Slovenia's Karst" landscape has hundreds of subterranean caves. Two of the most fascinating (and best-exploited) cave systems are Postojna and Skocjan, both filled with unbelievable limestone formations, and colored by different minerals, the result of thousands of years of rainwater seeping through the surface of the earth into the underground chambers. Over the eons, these drops of water have caused stalactites and stalagmites to mushroom throughout these vast otherworldly spaces where underground rivers, secret lakes, immense tunnels, and rock-hard formations that look like melted wax form the backdrop against which an unusual albino creature has evolved in almost complete isolation from life above the earth's surface.

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