List of castra

Castra (Latin, singular castrum) were military forts of various sizes used by the Roman army throughout the Empire in various places of Europe, Asia and Africa.

The disposition of the castra reflects the most important zones of the empire from a military point of view. Many castra were disposed along frontiers particularly in Northern and Central Europe. Another focal point was the Eastern border, where the Roman Empire confronted on of its long-term enemies, the Persian Empire. Other castra were located in strategically important zones, as in Egypt, from which most of the wealth of the empire came. Finally, other castra were located in zones in which the Romans experienced local unrest, such as Northern Spain and Judea. Provinces where the Roman power was unchallenged, such as Italy, Gaul, Africa and Greece, were provided with few or no castra.

In the long history of the Roman Empire, the character of the military policy of the Roman Empire changed, and consequently the location and dimension of the castra changed. Under Emperors Gallienus and Aurelian (and later Diocletian), the Roman army was organized into a high-mobility central army (the comitatus) and in local troops (the limitanei). Some castra lost importance, others were built in new zones, and in general they lost the role of permanent quarter for huge corps of troops.

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