Built into the Northern face of Panayor Hill at the end of Harbour Street the theatre rises 30m, is 145m wide and can seat 25,000 people.
A much older (and smaller) Hellenistic theatre may have been on this site from around 200 BC but the theatre seen today dates to the Roman period and was constructed in the 1st century AD and expanded and altered up to the 5th Century to form the current layout.
The theatre has 66 rows of seats divided by two walkways forming three horizontal sections. The steepness of the rows seems to increase above each section which was probably for the benefit of those sitting at the back of the theatre.
In the 4th Century AD a wall was constructed around the base of the theatre to protect the audience from wild animals and from possible injury during gladiatorial and other events. This area was also waterproofed so if necessary it could be filled with water.
The stage building facing the audience would have been richly decorated with columns, windows and statues.
The theatre was used not only for concerts and plays, but also for religious, political and philosophical discussions as well as gladiator and other events involving wild animals.
Earthquakes damaged the theatre during the 4th Century after which it apparently was only partially repaired until in the 8th Century the building was incorporated into the cities defences.