Check why is this Slovenia’s most popular attractions! If you’re visiting Slovenia you can’t miss a Postojna cave! This fantastic and magical underground cave system is the most visited tourist cave in Europe. A legendary tourist train takes you to the underground network of karst tunnels, galleries, and halls. Simply a must see attractions for all family members! Meet the queen of the caves! If you are visiting Slovenia, this is definitely a must-do for your kids and all family members. During a guided tour and exploring the fascinating network of subsurface caves, you will also learn everything about the most important karst features, see the largest, 5-metre high stalagmite and much more. You can also visit the oldest underground post office in the world and the most famous underground animal – the human fish (proteus). Postojna Cave and its exciting interior will take you on a fantastic journey beneath the surface of the Earth. Thus, it is no wonder that it has, during the 200 years since it was opened to the public, hosted over 37 million visitors from all over the world. In addition to the two world-famous attractions, the Postojna Cave Park offers a number of other experiences, perfect for an all-day trip that you will remember for years to come. Predjama Castle is situated in the middle of a towering cliff, a mere 9 km from Postojna Cave. Picturesque, magnificent, defiant, mysterious and impregnable, it has been dominating the surrounding area, perched high up in the 123-metre high cliff, for more than 800 years. It is listed among the Guinness World Records as the largest cave castle in the world.