Built in the 1st century BC on the remains of the Greek theater, the theater is located behind the Temple of the Dioscuri and is only partially visible. Suetonius recounts that Nero performed there as a singer, and it could host about 5,000 spectators. It was renovated several times, abandoned in the Middle Ages, later overtaken by buildings, and then partially destroyed with the opening of Vico Cinquesanti (1569-74). The visit allows one to appreciate sections of the ambulatory, the cavea, and the scene, while the arches on the upper decumanus gave their name to the street of Anticaglia.

Installation n°. 536