Odysseus leaves Troy with twelve ships. Homer’s Odyssey begins its account of the hero’s return by describing him sailing from Troy with his fleet and crew after the Trojan War.
The voyage quickly goes wrong. Odysseus and his men raid the Cicones at Ismarus, but a counterattack forces them back to their ships. Storms then drive the fleet far off course, beginning the long journey through the lands of the Lotus-Eaters, the Cyclops, Aeolus, Circe, and others.
The number twelve refers to Odysseus’s original fleet, not to the number of ships that eventually reach Ithaca. His crews are gradually lost through warfare, shipwreck, divine punishment, and their own mistakes. After the episode involving the cattle of Helios, Zeus destroys the final ship, leaving Odysseus as the sole survivor.
A common mix-up is confusing Odysseus’s twelve ships with the much larger Greek force that sailed against Troy, or with the single ship provided by the Phaeacians for his final journey home.