One of the best cave systems open to the public is situated on the outskirts of Ioanina. It was only discovered during World War II when a shepherd was looking for a shelter from bombing raids. The explored part of the caves extends for some miles, with more yet to be discovered in what is believed to be the largest cave network in Greece. Parts of these are open to visitors, but only on a guided tour.

The guides illuminate and pick out some of the more striking stalactites and stalagmites, including natural rock formations said to resemble such objects as the Statue of Liberty, The Leaning Tower of Pisa, and the Sphinx.