On Unbelievable Stories (39)

What is said about Cerberos is that he was a dog with three heads. It is clear that, just like Geryon, he too was from the city called Trihead and so people would say, That’s a large and handsome Triheaded hound! It is said that Heracles led him up out of Hades: such a myth!

What happened was something like this. Guarding his cattle Geryon had two large, spirited dogs whose names were Cerberos and Orthos. Orthos was done away with by Heracles in Trihead after he had rounded up the cattle. Cerberos, meanwhile, went along with the herd. Wanting the dog, a Mycenaean man by the name of Molottos first asked Eurystheus to give him the dog. After Eurystheus refused, Molottos persuaded the herdsmen to let him keep the dog penned up in a cave on Cape Tainaron in Laconia. Because Cerberos sired excellent offspring, he would lower down female dogs for him to mount.

Eurystheus sent Heracles on the hunt for the dog. Having wandered the whole Peloponnese, he arrived at the place where he had been tipped off that the dog was to be found. He descended into the cave and led the dog out. And so people would say, Having descended through a cave into Hades, Heracles led the dog up out of there.