There is no surviving account in ancient Greek literature of of stories as important as the fall of Troy or Theseus and the Minotaur. It is to visual sources that we have to turn for much of our knowledge of the myths. Vase paintings, engraved gems and sculpture in bronze and and stone often pre-date reference to the myths in literature or offer alternative versions to the familiar accounts; always they throw light on the way the Greeks understood the stories of gods and heroes.