The Fortress of Perperikon is located 20 kilometres north-east of the town of Kudjali in Southern Bulgaria. After examining some ancient mapsm Bulgarian scientists have revealed the ancient name of the grandiose religious centre Perperikon as "Pergamon" - a Thracian word meaning "stronghold on the top" - thus unveiling one of the deepest secrets of the ancient world. According to the Bulgarian scientists the name of the city came from the presence of such a fortress...
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