Io was another woman to whom Zeus fell in love and made her suffer. She was a beautiful girl living in Argos, central Greece, when Zeus saw her and fell madly in love. Disguised into a cloud, Zeus made love to her. His jealous wife, however, Hera, learnt about this relationship and turned Io into a cow to keep her away from her husband. Io was about to suffer many misfortunes until she was finally turned into a woman again and have a normal life.
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Discover the myth of Io and Zeus
Io was the daughter of Inachus, one of the River Gods and king of Argos. She was a beautiful, young girl and a priestess of goddess Hera. However, one day, great god Zeus saw her and fell madly in love with this maiden. Io was constantly avoiding his amorous attempts, until Zeus took the form of clouds, surrounded her and made love to her. Unfortunately, his jealous wife, Hera, learned about this relationship and turned Io into a white cow to punish her and stop them from getting involved.
The hundred-eyed dog Argus
Io was tied to an olive tree in Heraion, the holy temple of Hera outside Argos, and the fierce hundred-eyed dog, Argus Panoptes, was guarding her and keeping Zeus away. However, Zeus found the way to set Io free and disregard his wife without doing it in person. He sent Hermes, the messenger god, to kill Argus, which was an extremely difficult task, since Argus always had fifty eyes open and fifty at sleep.
Hermes took the form of a shepherd who is good at music and story telling. Using his skills, Hermes lulled all hundred eyes of Argus to sleep and killed him. Mythology has it that Hera took all the hundred eyes of Argus and placed them on the tail of her favourite bird, the peacock, which was her symbol.
Transforming Io into a cow
Hera could not bear the humiliation any more. She then sent a gadfly to sting bovine Io continually until she got mad. Indeed, Io was wandering from country to country like a mad cow, always being stung by the gadfly. During her journey, she crossed the path between Propontis and the Black Sea. Since then, this path was named Bosporus, which means "the passage of the cow".
After a while, in Mount Caucasus, she met the Titan Prometheus, who was chained by Zeus. Prometheus was punished by the Master of the Gods for giving the fire to the humanity, since until then the fire was a privilege only to Gods. Prometheus thus was sentenced to be chained on the rocks for ever. Every day, an eagle would come to eat his liver. The liver would grow again in the night and next morning the eagle would come again to eat it. This torment would continue for eternity.
The prophecy of Prometheus
Io, thus, met chained Prometheus during her journey, who gave her comfort. He predicted that, one day, Io would take back her human form, bear children from Zeus and one of her descendants would come to free Prometheus from his torture. After many years of wandering, Io eventually reached Egypt, where Zeus gave her back her human form.
Io bore a son, Epaphus, and a daughter, Keroessa, from Zeus. According to mythology, Epaphus later founded the town of Memphis in Egypt, which he named after his wife. Keroessa mated with sea god Poseidon and gave birth to a son, Byzas, who would later found the town of Byzantium, now known as Constantinople.
The descendants of Io
Io eventually married Telegonus, the king of Egypt, and their grandson, Danaus, would return to Greece with his fifty daughters, the Danaides. Eleven generations afterwards, one of Io's descendants, the legendary Hercules, would set Prometheus free from his chains. The descendants of Io would also make the royal houses of Thebes and Argos.