The Roman fortress of Diana on the Danube is the best preserved Roman military fortress that was part of the border of the Roman Empire - Limes. A significant area of the fortification was explored and the outer ramparts with massive gates protected by outer towers, the main headquarters (Principia), the porch of the main headquarters (Via principalis), the officers' palace (Praetorium), barracks for soldiers (Contubernium) and the bathroom (Terme) were found.