Thermae be applied to those magnificent edifices which grew up under the empire, in place of the simple balneae of the republic, and which comprised within their range of buildings all the appurtenances belonging to the Greek gymnasia, as well as a regular establishment appropriated for bathing. Writers, however, use these terms without distinction. Thus the baths erected by Claudius Etruscus, the freedman of the Emperor Claudius, are styled by Statius "balnea", and by Martial "Etrusci thermulae". In an epigram by "Martial"—"subice balneum thermis"—the terms are not applied to the whole building, but to two different chambers in the same edifice.
Thermae A public bath was built around three principal rooms: the "caldarium" (hot bath), the "tepidarium" (warm bath) and the "frigidarium" (cold bath). Some "thermae" also featured steam baths: the "sudatorium", a moist steam bath, and the "laconicum", a dry hot room much like a modern sauna. By way of illustration, this article will describe the layout of Pompeii's Old Baths adjoining the forum, which are among some of the best-preserved Roman baths. The references are to the floor plan pictured to the right. The whole building comprises a double set of baths, one for men and the other for women.