The Roman theatre of Philippopolis (Latin: Theatrum Trimontense; Bulgarian: Пловдивски античен театър, Plovdivski antichen teatar) is one of the world's best-preserved ancient Roman theatres, located in the city center of modern Plovdiv, Bulgaria, once the ancient city of Philippopolis. It was constructed in the 1st century AD, probably during the reign of Domitian. The theatre can host between 5,000 and 7,000 spectators and it is currently in use.
Ref.: https://en.wikipedia.org/wiki/Roman_theatre_of_Philippopolis