Of the ancient theatre very little remains, having been engulfed by buildings from later periods and hidden from the square. You can only see the remains of a wall in opus incertum relevant to the "cunei" - the radial walls of the auditorium which supported the steps - some of which are still preserved in the basements of the houses and are difficult to access.
According to the findings and analysis of aerial photographs, the theatre was built in the 1st century AD and had a diameter of about 75 meters with a capacity of about 4,000 seats. Some foundation structures still lie beneath the city hall and the square. The stage and the orchestra areas were almost certainly destroyed in the next period in order to reuse the building material. A stone slab placed in the bell tower of the basilica of San Pelino has an ancient inscription now eroded, regarding the construction of the public building: "T. MITTIUS. P(ublius). F(ilius) .CELER. IIIIVIR QUINQ(ennalis) THEATRUM .MUNDUM. GRADUS. FACIENDOS. CURAVIT" - meaning that the five-year quattuor vir called T. Mittius Celere oversaw the construction of the theatre, the steps and a "mundus".
Historical NotesThe theatre, located in the historical centre on the site that is now the town's main square, was built in the first century BC using the natural hill form of the land of the ancient citadel.
Unfortunately, little remains of the original structure which was obliterated over the centuries by the construction of buildings and, more recently, the opening of the road which also partially altered the shape of the square. It was the shape of the latter, defined by the surrounding houses arranged in a semicircle, which suggested its existence, later confirmed by finds in and around the medieval buildings.
Looking at the southern side of the square, in fact, we can see some lower buildings with small oval windows, leaning up against older and bigger buildings arranged in a semicircle - the curvature of which is particularly noticeable on the back. These are typical structures from the Middle Ages which took advantage of the high base of the ancient walls of the Roman theatre.