The emperor Caracalla had this vast baths complex inaugurated in 212 CE. It spread across 10 hectares, comprising baths, gyms, libraries, shops and gardens, and was used by up to 8000 people daily. The ruins are still vast, impressive, with few visitors, and to see how they once would have been, you can hire a virtual reality headset from the ticket office. The focal point is the central bathhouse, a huge rectangular edifice bookended by two palestre (gyms).
The bathouse was centered on a frigidarium (cold room), where bathers would stop after the warmer tepidarium and dome-capped caldarium (hot room). While the customers enjoyed the luxurious facilities, below ground hundreds of slaves sweated in a 9.5km tunnel network, tending to the complex plumbing systems.The baths remained in continuous use until 537 CE, when the Visigoths cut off Rome's water supply. Excavations in the 16th and 17th centuries unearthed important sculptures, many of which found their way into the Farnese family's art collection.
In summer, the ruins are used to stage spectacular music and ballet performances.
Note that the ticket office closes one hour before the site closes.
