Thermae would be heated by a log fire before being channelled into the hot bathing rooms. The design of baths is discussed by Vitruvius in "De Architectura". "Thermae, balneae, balineae, balneum" and "balineum" may all be translated as "bath" or "baths", though Latin sources distinguish among these terms. "Balneum" or "balineum", derived from the Greek signifies, in its primary sense, a bath or bathing-vessel, such as most persons of any consequence among the Romans possessed in their own houses, and hence the chamber which contained the bath, which is also the proper translation of the word "balnearium". The diminutive "balneolum" is
Roman ruins of Pisões thick wall. The masonry and wedge bricks are specially constructed to support the structure, with gaps sealed with small stones. The dam closes a hydrological basin that extends to Beja, covering an area of . It is assumed that the reservoir created from this dam occupied a length of and area of , holding a volume . The dam helped to supply water for agriculture and recreational purposes (including the swimming pool and thermae) in the villa. Roman ruins of Pisões The Roman Ruins of Pisões (), is an important Roman villa rustica located in the civil parish of Beja