Greco Roman Theatre, Italy

The similarities of Roman theatres to those of earlier Greek theatres are due in large part to the influence of Ancient Greece on the Roman triumvir Pompey. Indeed, much of the architectural influence on the Romans came from the Greeks, and theatre structural design was no different from other buildings. However, Roman theatres have specific differences, such as being built upon their own foundations instead of earthen works or a hillside and being completely enclosed on all sides. Roman theatres derive their basic design from the Theatre of Pompey, the first permanent Roman theatre. The proscaenium was a wall that supported the front edge of the stage with ornately decorated niches off to the sides. The Hellenistic influence is seen through the use of the proscaenium. The Roman theatre also had a podium, which sometimes supported the columns of the scaenae frons. The scaenae was originally not part of the building itself, constructed only to provide sufficient background for the actors. Eventually, it became a part of the edifice itself, made out of concrete. The theatre itself was divided into the stage (orchestra) and the seating section (auditorium). Vomitoria or entrances and exits were made available to the audience.  Source