Join 科学与技术 upcoming events being held in Postojna. Postojna is a charming city in Slovenia, known for its stunning natural beauty, most notably the incredible Postojna Cave, a vast network of karst cave formations featuring impressive stalactites and stalagmites, as well as the indigenous olm, or proteus, a type of aquatic salamander found only in a few locations worldwide, making it an ideal destination for nature enthusiasts and adventure-seekers.