The Roman Emperor Caracalla built the second largest baths in Rome known as the Baths of Caracalla in the 3rd century. The baths included many rooms offering different temperatures and facilities like swimming pools, dry and steam saunas, gardens, and places to socialize, relax, read and exercise. An earthquake, looting and negligence turned the complex into ruins, but nowadays the Rome Opera hosts its summer ballets and operas inside the ruins. If you are a history buff, you will fall in love with this place.