The Thermae Antonianae, one of the largest and best preserved examples of an ancient spa complex, was constructed under the auspices of the Emperor Caracalla in the southern part of the city. The building was finished in 216 A.D. and exhibits the rectangular plan typical of Imperial spa centres. The spa itself was not simply a place for bathing, sport and health, it was also a place of study and for relaxing. Entrance to the heart of the building was by one of four porticos on the north-east face. Around the centre of the structure the various parts of the spa are found in sequential order: the "Calidarium", the "Tepidarium", the "Frigidarium" and the "Natatio". There are also other zones and areas to be found around the two gymnasiums. The spa of Caracalla is one of those rare ancient.