Perperikon
Perperikon (Bulgarian: Перперикон), also Perpericum, is an ancient Thracian city located in the Eastern Rhodope Mountains, 15 km northeast of the present-day town of Kardzhali, Bulgaria on a 470 m high rocky hill, which is thought to have been a sacred place. The village of Gorna krepost ("Upper Fortress") is located at the foot of the hill and the gold-bearing Perpereshka River flows nearby.