The world-renowned beauty of Postojna Cave is one of Slovenia's pearls. A special train will take you deep into this magnificent underground world. Here you will see unusual sculptural rock formations, magical stalactites and stalagmites, underground halls and strange animals, the most famous and unique one being the human fish (Proteus anguinus). Not far from the queen of caves, in a rocky wall above an underground cave stand the king of all castles – Predjama Castle, the largest cave castle in the world