# Orthrus
**Orthrus** (Ὄρθρος; also spelled Orthus or Orthos, Ὄρθος) was a two-headed dog of [Greek mythology](https://www.edgepedia.org/greek-mythology), a son of the monsters Typhon and [Echidna](https://www.edgepedia.org/echidna-mythology), who guarded the red cattle of the giant Geryon on the island of Erytheia and was killed by Heracles during the hero's tenth labor.[1](https://www.theoi.com/Ther/KuonOrthros.html) • [2](https://www.greekmythology.com/Myths/Monsters/Orthrus/orthrus.html)
| Key fact | Detail |
|---|---|
| Form | A two-headed dog, one head fewer than his brother Cerberus; some accounts also give him a serpent's body or tail[3](https://users.sch.gr/ipap/mixogeni/209.htm) • [1](https://www.theoi.com/Ther/KuonOrthros.html) |
| Parents | Typhon (Typhoeus) and Echidna, per Hesiod (*Theogony* 309), Apollodorus (2.106), and Quintus Smyrnaeus[1](https://www.theoi.com/Ther/KuonOrthros.html) |
| Siblings | Cerberus, the Chimera, and the Lernaean Hydra[3](https://users.sch.gr/ipap/mixogeni/209.htm) |
| Offspring | The Sphinx of Thebes and the Nemean Lion, by the Chimera (Hesiod, *Theogony* 326)[1](https://www.theoi.com/Ther/KuonOrthros.html) |
| Role | Watchdog of Geryon's red cattle on Erytheia, together with the herdsman Eurytion[1](https://www.theoi.com/Ther/KuonOrthros.html) |
| Death | Killed by Heracles with his club when the hero came to steal the cattle[2](https://www.greekmythology.com/Myths/Monsters/Orthrus/orthrus.html) |
## Family and offspring
Ancient sources agree in making Orthrus a child of the pair of arch-monsters Typhon and Echidna. Hesiod's *Theogony* (line 309), the mythographer Apollodorus, and Quintus Smyrnaeus all list this parentage.[1](https://www.theoi.com/Ther/KuonOrthros.html) Through this line he belongs to the same monstrous brood as Cerberus, the hound of Hades; the Chimera, the lion-goat-serpent hybrid; and the many-headed [Lernaean Hydra](https://www.edgepedia.org/lernaean-hydra).[3](https://users.sch.gr/ipap/mixogeni/209.htm)
Hesiod adds a strange second generation. In *Theogony* 326 the Chimera, in love with Orthrus, mothered the deadly Sphinx and the Nemean Lion.[1](https://www.theoi.com/Ther/KuonOrthros.html) A Greek mythological account draws the connection further: the Sphinx, itself born of an incestuous union, later brought about the incestuous marriage of Oedipus and Jocasta at Thebes.[3](https://users.sch.gr/ipap/mixogeni/209.htm)
## Guarding the cattle of Geryon
Orthrus's only mythological role is as the guard of Geryon's herd. Geryon, a three-bodied giant who lived on the island of Erytheia in the far west, near the boundary of Europe and Libya, kept a herd of red cattle. The herd was tended by the herdsman Eurytion and watched by the two-headed dog.[4](https://www.perseus.tufts.edu/Herakles/cattle.html) • [5](https://mythoi.org/ehidna/) A comparison with his brother is built into the sources: as Cerberus guards the house of Hades, Orthrus guards the cattle of Geryon.[5](https://mythoi.org/ehidna/)
## The tenth labor of Heracles
Eurystheus ordered Heracles to fetch Geryon's cattle as the hero's tenth labor, a journey to the edge of the known world.[4](https://www.perseus.tufts.edu/Herakles/cattle.html) According to Apollodorus (*Library* 2.5.10), when Heracles reached the island the dog rushed at him and Heracles struck it down with his club; he then killed the herdsman Eurytion when he came to help.[2](https://www.greekmythology.com/Myths/Monsters/Orthrus/orthrus.html) A herdsman reported the events to Geryon, who attacked Heracles as he was escaping with the cattle and was killed by the hero's arrows.[4](https://www.perseus.tufts.edu/Herakles/cattle.html) Heracles then drove the herd back to Greece, a return journey marked by further adventures, and delivered the cattle to [Eurystheus](https://www.edgepedia.org/eurystheus), who sacrificed them to Hera.[4](https://www.perseus.tufts.edu/Herakles/cattle.html)
## Name and word
The dog's name appears in two forms in ancient texts. Hesiod's *Theogony* (line 309) and Apollodorus' *Bibliotheca* (2.5.10) give the name as Orthos (Ὄρθος), while the form Orthros (Ὄρθρος) is also standard, and English renderings include Orthrus and Orthus.[2](https://www.greekmythology.com/Myths/Monsters/Orthrus/orthrus.html) • [6](https://mundus.mythscribe.cloud/entries/orthrus/) The common Greek noun ὄρθρος is a separate word meaning daybreak, dawn, or cock-crow, the time just before or about daybreak.[7](https://atlas.perseus.tufts.edu/dictionaries/entry/urn%3Acite2%3Ascaife-viewer%3Adictionaries.v1%3Alsj-n75052/)
## In ancient art and later literature
Orthrus appears in Greek vase painting of the Geryon episode. An Athenian black-figure amphora of the 6th century BC in the Harvard Art Museums shows the two-headed dog, and a Chalcidian black-figure amphora from South Italy of about 540 BC, now in the [Bibliothèque nationale de France](https://www.edgepedia.org/bibliotheque-nationale-de-france), depicts Heracles fighting Geryon with Orthrus lying upside down at the lower left and Eurytion fallen beside him.[1](https://www.theoi.com/Ther/KuonOrthros.html) • [8](https://worldofcreatures.org/creatures/orthrus/) Some descriptions and depictions give him a serpent tail or serpent body alongside the two heads.[1](https://www.theoi.com/Ther/KuonOrthros.html) • [9](https://s3-eu-west-2.amazonaws.com/parikiaki-cdn-1/wp-content/uploads/20191108093606/ALL-PAGES15.pdf)
The late-antique poet Quintus of Smyrna, describing Heracles' deeds in the *Fall of Troy* (6.249–255), shows the slain Geryon among his cattle with the hound Orthros lying dead in front of him, "like Cerberus his brother-hound".[2](https://www.greekmythology.com/Myths/Monsters/Orthrus/orthrus.html) Modern scholarship on the myth notes that Orthrus, like Cerberus, was typically depicted as a dog with a twin-headed snake-tail, and reads his role as that of a herding dog protecting Geryon's cattle from thieves; the episode has been interpreted as analogous to a *katabasis*, a descent to an otherworldly realm beyond the stream of Ocean.[10](https://api.research-repository.uwa.edu.au/ws/portalfiles/portal/47011927/THESIS_DOCTOR_OF_PHILOSOPHY_FLOKY_Aaron_Robert_Joseph_2018.pdf)
## References
1. [ORTHRUS (Orthros) - Two-Headed Dog of Greek Mythology, Theoi Project](https://www.theoi.com/Ther/KuonOrthros.html)
2. [Orthrus, GreekMythology.com](https://www.greekmythology.com/Myths/Monsters/Orthrus/orthrus.html)
3. [ΟΡΘΡΟΣ ή ΟΡΘΟΣ (διφυής), Ελληνική Μυθολογία](https://users.sch.gr/ipap/mixogeni/209.htm)
4. [Hercules' Tenth Labor: the Cattle of Geryon, Perseus Digital Library](https://www.perseus.tufts.edu/Herakles/cattle.html)
5. [Έχιδνα μυθολογία, Ελληνική Μυθολογία](https://mythoi.org/ehidna/)
6. [Orthrus, Mythscribe Mundus](https://mundus.mythscribe.cloud/entries/orthrus/)
7. [ὄρθρος, LSJ, Scaife ATLAS](https://atlas.perseus.tufts.edu/dictionaries/entry/urn%3Acite2%3Ascaife-viewer%3Adictionaries.v1%3Alsj-n75052/)
8. [Orthrus, World of Creatures](https://worldofcreatures.org/creatures/orthrus/)
9. [Ancient Greek Mythical Monsters (PDF)](https://s3-eu-west-2.amazonaws.com/parikiaki-cdn-1/wp-content/uploads/20191108093606/ALL-PAGES15.pdf)
10. [Aaron R. J. Floky, doctoral thesis on monstrous canines in Greek myth, University of Western Australia (2018)](https://api.research-repository.uwa.edu.au/ws/portalfiles/portal/47011927/THESIS_DOCTOR_OF_PHILOSOPHY_FLOKY_Aaron_Robert_Joseph_2018.pdf)
---
*Topic: Encyclopedia › Society and history › Philosophy, religion, and mythology › Mythology and folklore › Greek mythology › Mythical creatures and monsters*
*Initially written Sep 17, 2026 · Reviewed: Sep 18, 2026; Sep 30, 2026; Oct 25, 2026 · Edited: Sep 18, 2026; Sep 30, 2026; Oct 25, 2026 · Last review: Oct 25, 2026*
*Copyright 2026 EdgeChat AI, a subsidiary of Biostate AI.*
License: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license