Euryale was born, along with her two sisters, to Phorkys and Keto, deities of the sea, in caverns beneath Mount Olympus, the home of the Olympians. Euryale and her sisters were not born gorgons. Medousa and Poseidon had had an affair in the temple of Athena, which angered Athena because she was a virgin goddess. Athena turned Medousa into a gorgon along with Stheno and Euryale, who were with Medousa, also got transformed into gorgons.