The Theatre of Dionysus is an impressive ruin on the southern slope of the Acropolis in Athens. You can climb up and sit in the semi-circle of marble seats ringed around the stage area. In its heyday, around the 4th century BC, the theatre could seat 17,000 people. You can still see names of the important people inscribed on the throne like seats in the front row (although this area is roped-off to conserve it). It was in this theatre that the plays of Sophocles, Euripedes, Aeschylus and Aristofanes were performed.
Dionysus was the Greek god of wine, agriculture and theatre, known to the Romans as Bacchus, hence the word Bacchanalia. The theatre is in the area of the Sanctuary of Dionysus, which also housed temples to the god. Excavations in the late 1800s rediscovered this important site and the Greek Government has recently announced its intention to restore the theatre.