The Pannonian Limes is a 420 km long part of the Danubian Limes which is the line of fortifications of the Roman legion extending along the Danube. Pannonia was the name of a Roman province whose northeastern border was the Danube River. The Roman Empire ruled the region from the middle of the century from the first AD to the fifth century.
The fortresses protected Pannonia from attacks by the barbarians from the north.
The line had different types of positions:
Camps for legionnaires (Castrum )
The 33 signs are in the 15th of March square in Budapest, where the Roman fort Contra-Aquincum was
About the signs
The rectangular signs are made of metal, and extend the entire length of the square. The Danube River is indicated by two lines with the signs representing the camps on both sides of the river.
In addition to the name of the camp, there is an illustration on the signs indicating the type of fortress, camp or citadel.