 The region was very rich in iron, which had been extracted in the area since the Iron Age by Thracian tribes.The Dacian fortresses of Orăştie mountains, most notably Sarmiszegetusa, which became the most important religious and political center of Dacia, was located close to Hunedoara and was supplied by the iron produced here.The remains of eight Dacian iron furnaces have been found at the Sânpetru hill near the castle.