The Hydra lived in the swamps near to the ancient city of Lerna in Argolis. It was a terrifying monster with the body of a serpent and lots of heads! Unfortunately the Hydra couldn’t be hurt by any weapon. If one of its heads were chopped off then another would grow in its place. It is also said that the breath of the Hydra was poisonous, it could kills a man. The Hydra would leave the swamp to attack herds of cattle and local villagers.