Described in the first world's encyclopedia Naturalis Historia, Vjetrenica is one of the largest caves in Europe. Much of it has not been even explored yet, but the accessible part offer an insight into the wonders of the underground world. Rich in fauna, with numerous natural decorations in form of stalactites and stalagmites, with lakes and rivers, Vjetrenica really seems as the place from the fairytale. Our tour starts in Mostar. On the way we visit Radimlja, medieval necropolis whose tombstones date back even to one thousand years ago. Richly decorated, these tombstones reveal the life in Bosnia-Herzegovina in the medieveal times. Upon visit to Vjetrenica, we visit Zavala, nearby Orthodox monastery carved deep in the rocks. Zavala's mysterious monks will welcome us as we pass through the tunnels and stairways of this beautiful monastery.