Medusa was the only mortal of the 3 monster sisters, who were given the generic name "Gorgons" in ancient Greek mythology. According to the tale, they lived in the West, near the shores of the river Oceanus.
Medusa had the ability to turn anyone who dared look into her eyes into stone. In Ovid's "Metamorphoses", it is told how Perseus beheads the Gorgon, by looking at her reflection in a copper shield. The winged horse Pegasus arose from the blood of Medusa.
Medusa the Gorgon is an extremely popular character in ancient art. Often her likeness can be seen on black-figure Corinthian vases, where she is portrayed as a woman with snakes instead of hair and having the tusks of a boar. She was also drawn on shields. Caravaggio's famous painting of her was also done on a round canvas.
The Gorgons were creatures born of the love between the sea deities Keto and Phorcys. Homer only mentions one Gorgon, while Hesiod wrote of 3 sisters, whose names were Stheno, Euryale and Medusa. Medusa was the youngest and only mortal of the 3.
According to the legend, the 3 Gorgons were once beautiful sea maidens. Poseidon, god of the sea, took a liking to Medusa but the Olympian gods became infuriated that he had become fond of a mortal.
Medusa's joyous laughter and beauty brought about Athena's wrath and she transformed her and her sisters into horrible winged monsters covered with scales, with snakes instead of hair and huge yellow tusks, like those of a boar.
The 3 sisters hid on a remote island and the people forgot about their beauty, terrified of their new forms. All waited for the hero that would save the world from the hideous Medusa, who turned everything into stone.
A hero did eventually appear, Perseus, with Athena herself gifting him a copper shield. From the sea nymphs, the hero received the Cap of Invisibility and the Winged Sandals.
After he cut off the head of Medusa, Perseus presented it to Athena, and she gave the blood to the God of medicine, Asclepius. The blood which poured out from the left side of the head of the Gorgon was poisonous but the blood that poured out from the right side was used by Asclepius to heal people.