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 Thermae (Varna) and Baths of Diocletian in the imperial capital Rome and the baths of Trier. The thermae are the largest in the Balkan region and the biggest surviving ancient building in what is today Bulgaria. The Roman Thermae of Varna feature the whole range of facilities including a "apodyterium" (changing room), a "frigidarium" (cold pool), a "tepidarium" (warm pool) and a "caldarium" (hot pool) as well as a "palaestra" (a space with social and athletic functions). Heating was provided by means of a hypocaust, an underfloor heating system of pipes. Roman Thermae (Varna) The Roman Thermae (, "Rimski termi") are a