The building of Aspendos city which is even more famous than the city itself is the theatre. It bears all the characteristics of the Roman period theaters. It is among the Roman theaters on the earth, which have survived through the present day with best conditions. It has a semi circular plan, which is at the same time a characteristic of Roman theaters. According to an unearthed in scription, it was built by the architect Zeno, the son of Theodorus, during the reign of the emperor Marcus Aurelius (161-180 A.D.) Having a capacity of around 18.000 spectators, the cavea (sitting section for the spectators) is divided by a diazoma (connecting path) into two sections on top of one another. There is a longitudinal gallery in the upper section, which provides entry to the cavea from the upper section, and the entry was provided by arched passages. Cavea has also other entrances through passages opening to diazoma, from another gallery which is located on the same level as diazoma and which extends all along the building. The entries to Cavea from the lower section is provided with the covered side passages (paradoi). The name of the people to whom some of the sitting places were reserved were written by scraping.
The stage building of the theatre has multiple floors and it is high, again in accordance with the Roman style. The side of the building which faces the outside is simple. In the middle of this side is an arched staff entry, and there are the entrances for the spectators on both sides.
The part of the stage building which faces the spectators bears dense decorations. The stage has a part projecting 7m. towards the front and it is 1,5m. high. There are five stage doors on the surface of the stage, and below these, five small doors are placed. The wall of the stage background was decorated with two series of columns each of which rose on top of one another. In the openings left between these columns, there were niches surrounded by small columns and pedments placed on top of these columns. There were statues inside the niches. There was a large pediment above the second series of columns. This pediment was embroidered with a figure of “Dionysos”, placed among the plant motifs. The holes on the wall of the stage building reveals the fact that a shady spot built with a wooden frame was used.