<P> Asclepiades of Tragilos and Pseudo-Eratosthenes related a similar story, except that Zeus and Nemesis became swans instead of geese . Timothy Gantz has suggested that the tradition that Zeus came to Leda in the form of a swan derives from the version in which Zeus and Nemesis transformed into birds . </P> <P> Pausanias states that in the middle of the 2nd century AD, the remains of an egg - shell, tied up in ribbons, were still suspended from the roof of a temple on the Spartan acropolis . People believed that this was "the famous egg that legend says Leda brought forth". Pausanias traveled to Sparta to visit the sanctuary, dedicated to Hilaeira and Phoebe, in order to see the relic for himself . </P> <P> Two Athenians, Theseus and Pirithous, thought that since they were both sons of gods, both of them should have divine wives; they thus pledged to help each other abduct two daughters of Zeus . Theseus chose Helen, and Pirithous vowed to marry Persephone, the wife of Hades . Theseus took Helen and left her with his mother Aethra or his associate Aphidnus at Aphidnae or Athens . Theseus and Pirithous then traveled to the underworld, the domain of Hades, to kidnap Persephone . Hades pretended to offer them hospitality and set a feast, but, as soon as the pair sat down, snakes coiled around their feet and held them there . Helen's abduction caused an invasion of Athens by Castor and Pollux, who captured Aethra in revenge, and returned their sister to Sparta . </P> <P> In most accounts of this event, Helen was quite young; Hellanicus of Lesbos said she was seven years old and Diodorus makes her ten years old . On the other hand, Stesichorus said that Iphigeneia was the daughter of Theseus and Helen, which obviously implies that Helen was of childbearing age . In most sources, Iphigeneia is the daughter of Agamemnon and Clytemnestra, but Duris of Samos and other writers followed Stesichorus' account . </P>

Who freed helen when she was kidnapped by theseus