Orthus

Orthus is a figure from Greek mythology described as a monstrous two‑headed dog. In surviving ancient writings, Orthus is presented as the offspring of Echidna, the mother of monsters, and Typhon, making him a sibling of other famed beasts such as Cerberus, Hydra, and Chimera. He is chiefly associated with guarding the cattle of Geryon, a three-bodied giant who dwelt on the far western edge of the world.

In the myth of the Twelve Labors, Heracles encounters and slays Orthus during his quest to obtain the cattle of Geryon. This act is part of the wider series of feats by which Heracles secures the herd for Eurystheus. Variations exist among ancient authors regarding the exact sequence of events, but Orthus is consistently depicted as a guardian opposed to Heracles’ mission.

Orthus appears in comparatively few surviving myths and is sometimes mentioned only in lists of Typhon‑Echidna offspring. He has occasionally been conflated with other multi-headed dogs in later texts, but modern treatments typically distinguish him by his two heads and his role as a sentinel connected to Geryon’s cattle.

Because Orthus is a relatively minor figure, references to him are predominantly found in ancient poetry and vase painting rather than in the more expansive myth cycles centered on Cerberus or Hydra. He remains a minor but recognizable component of Greek myth’s broader pantheon of monsters.