Valetudinaria were hospital-like buildings built throughout the Roman Empire, from around the 100s BCE. Many have been discovered among the ruins of old Roman military fortresses. Like more modern hospitals, they were made up of a number of small rooms, divided by hallways. They are thought to have been for the relief of slaves and soldiers, and to have provided hospitality for travellers. Literary and archaeological evidence suggests there was one at Neuss, in the lower Rhine area of Germany. There is less evidence of civilian hospitals during this period - there were no buildings devoted entirely to the care of the sick until well into the Christian era.
However, it is not completely clear that the valetudinaria were hospitals in the way we understand the idea. The archaeological and written evidence does not make clear how they were used. Valetudinaria may have been places used to house visitors to Roman camps, or even barracks. Very few appear to have had latrines or what might have been operating theatres. They may simply have been storehouses.
P Baker, ‘The Roman Military Valetudinaria: Fact or Fiction’, in R Arnott (ed.), The Archaeology of Medicine Proceedings of the Theoretical Archaeology Group 1998 (Oxford: Archaeopress, 2002), pp 69-80
P Baker, Medical Care for the Roman Army on the Rhine, Danube and British Frontiers from the First through Third Centuries AD (Oxford: Hadrian Books, 2004)