If you love seeing cool structures then I think you’ll appreciate the architecture of this Cave Castle in Slovenia. Predjama Castle is in the town of Postojna, Slovenia and it is built into the cave opening on the side of a cliff about 400 feet above the ground. Legend has it that the caves contain a secret passage to a valley where Erazem Predjamski would go for food to keep his people from starving during the siege. The castles most famous owner was Erazem Lueger, a “Robin Hood” figure who took from the rich and gave to the poor.