In Greek mythology , two monsters that guarded the narrow passage through which Odysseus had to sail in his wanderings.
These waters are now identified with the Strait of Messina . On one shore was Scylla, a monster with six snaky heads, who reached out of her cave to seize and devour six of Odysseus' companions. On the opposite shore was Charybdis, the personification of a whirlpool, who drank down and belched forth the waters three times a day. The shipwrecked Odysseus saved himself by clinging to a tree on the shore until his raft floated to the surface.