Romans conceived of the public baths as spaces intended for the personal cleanliness and social relationships. Their organization corresponds to a functional structure, of linear way. Their rooms were combined with water at different temperature: following the changing room (apodyterium), there is cold water (frigidarium), warm (tepidarium), hot (caldarium) and a sauna (sudatorium or laconicum depending on whether or not it has steam).
They were heated up by the system of hipocastum or underground air chambers fed by one or several furnaces of refractory brick (praefurnium) under the rooms.
The construction of the Minor Roman Thermal Baths of Asturica must have taken place in the middle of the first century A.C, although at the end of the second century they were remodelled, to be abandoned in the middle of the third century. In one of the drains,closed by flat roof-tiles in a double slope, several jewels appeared, which indicates the preferential use by the privileged classes.