Cerberus
In Greek mythology, Cerberus (Greek: Κέρβερος, Kérberos; Latin: Cerberus) is the monstrous, multi-headed dog that guards the entrance to the Underworld, preventing the souls of the dead from leaving.
Often called the "hound of Hades", Cerberus was one of the numerous offspring of the monsters Typhon and Echidna; he is usually depicted as having three heads, along with a serpent for a tail.
Cerberus Media
Heracles, wearing his characteristic lion-skin, club in right hand, leash in left, presenting a three-headed Cerberus, snakes coiling from his snouts, necks and front paws, to a frightened Eurystheus hiding in a giant pot. Caeretan hydria (c. 530 BC) from Caere (Louvre E701).
Cerberus and Hades/Serapis. Heraklion Archaeological Museum, Crete, Greece.
Athena, Hermes and Heracles, leading a two-headed Cerberus out of the underworld, as Persephone looks on. Hydria (c. 550–500 BC) attributed to the Leagros Group (Louvre CA 2992).
Hercules and Cerberus. Oil on canvas, by Peter Paul Rubens 1636, Prado Museum.
Other websites
Media related to Cerberus (mythology) at Wikimedia Commons