trails inside the postojna cave park. it is the second-longest cave system in the country. one of its top tourism sites. the caves

ancient attraction beautiful building castle cave cavern caves caving cliff country created dark day deep defend europe formation fort fortress geologist geology grotto historic history inside interior its jama karst landmark landscape limestone medieval mineral mountain national nature old one park pivka postojna renaissance river rock secondlongest secret sites slovenia speleology stalactite stalagmite stone system top tourism tower trails travel underground wall water were