The ancient Odeon of Thasos, an conservatory in the ancient city of Thassos was built in Roman times. The building, which was discovered in 1929 gives us the impssion of a monumental building even though its biggest part is under the modern road of the town with only its lower part visible and the first rows of seats. It is certain that in ancient times it would have been an imposing edifice. It is made of marble and situated in the south of the ancient Agora.
The building consists of a hollow with two rows of seats, forming a semicircle, one orchestra and a stage structure. The orchestra is not paved and from the byways survived the two walls that support the ground at the edges of the hollow.
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.