Greek Mythology Notes

Cycnus of Troy

hero
Κύκνος
invulnerability

Son of Poseidon who was invulnerable to weapons and fought Achilles on the beach at Troy until strangled with his own helmet strap.

The Myth

No weapon could pierce his skin — so Achilles strangled him with the strap of his own helmet. Cycnus, son of Poseidon, defended the Trojan beach when the Greeks landed. Arrows bounced off him. Spears shattered. Achilles threw everything he had and nothing worked. Finally, Achilles tackled Cycnus and throttled him with his helmet chinstrap, the one part of his equipment that was not divine. As he died, Poseidon transformed him into a swan (kyknos). The fight established Achilles's dominance immediately upon arrival — even an invulnerable opponent could not survive him. It also foreshadowed Achilles's own vulnerability: the greatest warrior had his own fatal weak point.

Parents

Poseidon

Symbols

swanhelmet strapimpervious skin

Fun Fact

Cycnus (swan) gives us the constellation Cygnus and the concept of a swan song.

Words We Inherited

English words and phrases that trace back to this myth:

cygnus

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