Romans at the Wall

The Roman Army was huge, by the time the Empire sprawled from the deserts of the east to the cold wastes of the north it numbered some 24 legions of roughly 5000 men; at its height it numbered over 33 legions. That put 125,000 men, at least in armor; add to that the auxiliary forces which numbered about half again as much and the Empire put somewhere around 400,000 men in the field.

There were armed, armored, equipped, supplied and housed.