The mystic underground of the Postojna Cave, most notorious karst cave in the world, with the Predjama Castle, listed among the Guinnes World Records as the largest cave castle, and home to the local "Robin Hood", the brave robber baron Erazem. The guided tour of Postojna Cave will consist of a ride by electrical train and a walk through beautiful underground passages and chambers with spectacular drop stones, pillars, limestone curtains and other natural stone forms. Continue to the idyllic village of Predjama, where you will be amazed by our fairy tale medieval Predjama Castle, famous for its dramatic setting in the gaping mouth of a cavern halfway up a hillside. Learn about the legend of Erasmus - "Slovenian Robin Hood" and return to the port.