Odeon of Herodes Atticus (Herodeion) - Credit: Wikimedia Commons
The Odeon of Herodes Atticus (Greek: Ωδείο Ηρώδου του Αττικού; also called Herodeion or Herodion;The Biggest Cultural Event of the Year in Athens and It’s In Our Backyard!, 3/2/2018, "known locally as the Herodion" Greek: Ηρώδειο) is a stone Roman theatreOne variation of the Roman theater was the odeon, a small, completely roofed theater intended for poetry readings and music performances (for example, the Odeon of Herodes Atticus on the southern slope of the Athenian Acropolis). For more see: PhD. Christoph Höcker, Architecture, Concise History Series, Laurence King Publishing, 2000, , p. 23. structure located on the southwest slope of the Acropolis of Athens, Greece. The building was completed in AD 161 and then renovated in 1950. Read more on Wikipedia
Source: en.wikipedia.org