Burnt mounds as saunas, and the prehistory of bathing

The physical scale of buildings like the Baths of Caracalla give the clearest indication of the importance of bathing in the classical order of things – though whether what Romans did in the bath was always clean and decent may be an open question. But what about the prehistory of bathing, and particularly of bathing in steam? An answer is given here which links the historical and ethnographic record to burnt mounds, among the more common and puzzling types of north European site.