Harbor Street culminates at the Great Theatre of Ephesus. The size is a dramatic 475 feet wide and nearly 100 feet tall. The three tiers contain sixty-six rows of seats with a capacity for 24,000 people. The Greeks began construction in the 4th century BC during the Hellenistic period. The Romans expanded the theatre several times from the mid-1st century through the 2nd century AD. The Great Theatre is once again a venue for concerts. Modern performers have included Madonna, Elton John, Sting, Diana Ross and Joan Baez.