The ancient theatre of Elis is situated on the north of the agora, on an old fluvial terrace of the River Peneus, appropriately landscaped for the purpose. The theatre was built in the 4th century BC. Major damage, probably due to an earthquake during the Late Hellenistic period, led to the replacement of the west retaining wall with a new one. The theatre was also modified in Roman times.
The theatre boasts the somewhat rare feature of an earthen cavea. Only the access passageways to the upper cavea, the parodoi and a row of stone seats in the lower cavea were faced with stone. Six staircases, approximately one metre wide and paved with river pebbles, divided the cavea into seven cunei. Strong retaining walls supported the fill of the cavea, forming, together with the lateral compartments of the stage, the two parodoi of the theatre.The permanent stone stage building is one of the earliest in Greece. It also preserved one of the oldest proscenia (early 3rd c. BC), its façade once decorated with half-columns.
Large holes along the stylobate were used to set up the scenery. Behind the proscenium were the various spacious compartments of the stage, with the parascenia on either side. The originally circular orchestra was truncated by the construction of an elongated cistern from which rainwater was channelled through an older duct into the River Peneus.The traveller Pausanias, who visited Elis in the latter half of the 2nd c. AD, found the theatre abandoned. A century later the whole area was turned into a cemetery. This destruction, also visible in other parts of the ancient city, is connected to the invasion of the Heruli (267 AD).
References:The ancient Argos Theater was built in 320 BC. and is located in Argos, Greece against Larissa Hill. Nearby from this site is Agora, Roman Odeon, and the Baths of Argos. The theater is one of the largest architectural developments in Greece and was renovated in ca 120 AD.
The Hellenistic theater at Argos is cut into the hillside of the Larisa, with 90 steps up a steep incline, forming a narrow rectilinear cavea. Among the largest theaters in Greece, it held about 20,000 spectators and is divided by two landings into three horizontal sections. Staircases further divide the cavea into four cunei, corresponding to the tribes of Argos A high wall was erected to prevent unauthorized access into the theatron and may have helped the acoustics, but it is said the sound quality is still very good today.
Around 120 CE, both theaters were renovated in the Roman style.