The Theatre of Dionysus Eleuthereus is a major open-air theatre and one of the earliest preserved in Athens. It was used for festivals in honor of the god Dionysus. Greek theaters in antiquity were in many instances of huge proportions but, under ideal conditions of occupancy and weather, the acoustical properties approach perfection by modern test. We know that the theater of Dionysus in Athens could seat 17,000 spectators, and that the theater in Epidaurus can still accommodate 14,000.  It is sometimes confused with the later and better-preserved Odeon of Herodes Atticus, located nearby on the southwest slope of the Acropolis. Some believed that Dionysus himself was responsible for its construction.