Below are pictures from Skocjan cave, Slovenia. The Skocjan cave system is one of the largest in Europe. Named a UNESCO World Heritage Site in 1986, the caves house some of the largest underground canyons in the world, 5 kilometres of underground passages, and many waterfalls.
Pictures were taken by Rhett A. Butler, copyright 2008. While these photos are the property of mongabay.com, it may be permissible to use them for non-commercial purposes (like powerpoint presentations and school projects), provided that the images are not altered in any form. Please read this for more details. If you are interested in using an image in a publication please contact me.