Named for Emperor Caracalla, the baths were completed in the early 3rd century. The richness of decoration has faded, and the lushness can be judged only from the shell of brick ruins that remain. In their heyday, they sprawled across 11 hectares (27 acres) and could handle 1,600 bathers at one time. As such, these baths are the largest to survive from Rome's imperial era. Most tours start with a visit to the palestra or gym, followed by a look at the laconicum or Turkish bath. You can also view the caldarium which was the "boiling pot" section of the baths. Sweaty bodies cooled down afterward with a soak in the lukewarm waters of the tepidarium. The session for the Romans ended at the frigidarium with a dip in cold waters. These hot immersions and cold dips were followed by massages and rubdowns by slave boys, many of whom were also recruited for their sexual services to their Roman masters. There remain the ruins of an open-air natatio or swimming pool.