The Thracian city of Perperikon is 15 km northeast of the present-day town of Kurdzhali, on a 1542 ft high rocky hill. Human activity in the area dates back to 5000 B.C. The first traces of civilization on the hill date from the Bronze Age, while the ceramics found on the place date from the Early Iron Age. The area is also known for being the last sustainable vulture location where several types of the endangered species could be observed. So this is a great place to combine bird-watching, ancient culture and some mountaineering.