Also called “Moorish bath “or “Turkish bath “, a hammam is a steamroom. It allows practising Muslims to carry out their ritual cleansing and this explains why it was sometimes regarded as a “mosque annex”. For over a millennium, the hammam, along with the mosque and souk (market), was one of the essential elements of the Islamic city. Following the traditional model of the ancient Roman thermal baths, and intended for personal hygiene, the hammam plays a significant role in Muslim social life. According to the day and the hour, it is reserved for men or women when it does not have double facilities. There are baths in the princely Umayyad desert residences and in medieval citadels, public baths in towns or in the villages, private baths in urban patrician homes. The beauty and number of hammams were a subject of pride for a city. The architecture of the hammam includes certain traditional elements: the apodyterium is the dressing room and relaxation room, adjoining the latrines; a maze of more or less narrow corridors connect it to the central part of the bath which includes three rooms whose layout and dimensions have varied over the centuries; the frigidarium is an unheated transitional room where one undresses in winter; it is no longer, as in ancient times, the main room reserved for physical exercise; the swimming pool and the arena have disappeared. There are two heated rooms, one warm, the tepidarium; the other hot, the caldarium, which is equipped with semi-circular recesses that the personnel use when seeing to bathers’ needs. The dimensions of the last two rooms indicate how practices have evolved. While the dressing room is covered by a dome surmounted by a skylight and resting on a tambour with windows, the central part has no ventilation opening: heat is retained by strong thick walls on which vaults or domes inlaid with bottle ends, artistically placed in geometric patterns, provide light for the room. The hammam also has, in the annex, a boiler room and fuel storage space. Up to the 12th century heating was supplied by a hot water distribution system with ceramic pipes (hypocausts) embedded in the ground and walls: this system was later abandoned and replaced by chimney pipes, with rooms laid out along the central axis of the flue coming from the hearth. The Oriental bath has as its ancestor, in Syria, the Umayyad castle bath where the relaxation room became a reception room; this bath has a series of three rooms: the first unheated, the second one warm and the third one hot, a veritable oven, which is adjacent to the boiler room. Four centuries later, the urban bath has as its prototype a simplified version of the Umayyad bath. Plans are now variations on the layout and importance of each of the essential elements of the bath.