As Roman army conquered Djerdap Gorge and found itself in hostile territory, building a fortification became inevitable. This is how Diana Castrum was erected in 101 AD upon Emperor Traian’s request.
Only scarce evidence of this once important stronghold is on display now. Military barracks with headquarters (Principia) are uncovered as well as portico in central area and two towers connected with an arch forming a castrum gate most likely. Small town started to grow around the fortress with religious sanctuary, necropolis and martyrium that were uncovered in small parts only, unfortunately.