Excavations carried out in the 50’s by Enrico Fiumi uncovered one of the finest and most well-preserved Roman theatre in Italy. In the Middle Ages the theatre was reduced due to the construction of the defensive wall, so that the entrance to the theatre is no more visible. A quadrangular portico with an apse was added later to the theatre. Today the portico flanks the remains of the Roman Baths erected when the theatre was abandoned at the end of the 3rd century A.D.
The Theatre was commissioned by two members of the Caecina family, both Roman consuls during the reigns of Emperors Augustus and Tiberius. The cavea (the seating area) was built into a natural incline like Greek theatres and is composed of two tiers of steps: the lower cavea with 10 rows of seats in local limestone and the media cavea with 9 rows of seats in the same stone. The cavea seated from 1.800 to 2000 spectators.
Above the media cavea a semi-circular arched corridor(called crypta) with 11 doors, gave access to the seating area and probably supported the upper cavea, no longer visible. At the foot of the seating area stood the orchestra, a space originally designated to the musicians and choir but also reserved for illustrious citizens.
In Summer, the Theatre is the venue of an important international drama festival.