Apollo, son of Zeus and Leto and twin brother of Artemis, was the god of light, music and the arts, as well as of prophecy, healing, measure and harmony. He was born on the island of Delos, at the centre of the Cyclades, where the Delia festivals were held in his honour. After slaying the serpent Python, he founded the famous oracle in Delphi, where the Pythian Games were celebrated. Other important sanctuaries of Apollo existed in Amyclae (near Sparta), Bassae in Arcadia (Temple of Apollo Epikourios) and Didyma (Asia Minor). Apollo was traditionally portrayed as a beardless, ideal youth, holding a lyre and sometimes a bow, as he was not without his dark side, being the god of plague and a punisher of hubris. Some of his other epithets were Phoebus, loxias (in reference to his ambiguous oracles) and musagetes (leader of the Muses).