The significant archaeological remains which indicate that the site was used from the prehistoric era to the late Middle Ages were found at Gradina site. The oldest settlement which has so far been identified at Gardina site belongs to the Late Bronze Age Hallstatt a-b.
The earliest Roman fort Acuminicum, which can be bind to the commencement of limes building, developed at the complex of the Celtic oppidum itself. Simultaneously with the development of Acumincum as the fortress, at the foot of the fort, a part of the civil settlement was being developed as it was proved by the remains of buildings and movable archaeological findings in the wider countryside.
The fortress was built in the Middle Ages on the base of the Roman Acuminicum. As Castrum Zelenkamen (Greenstone) the fortification was quoted in the historical sources as yet in 1072.
At the beginning of 15th century, it was the part of property of great Serbian nobleman from the Branković`s family. It was occupied by the Turks in 1521. The remains of the fortress can be seen today both at the entrance of village Stari Slankamen and the on the hill north of it.