In March 1918, the U.S. Navy’s largest fuel ship left Barbados carrying 11,000 tons of manganese ore and 306 people, but it vanished without sending a single distress call: More than a century later, no confirmed trace of the ship has ever been found

The USS Cyclops vanished in 1918 after departing Barbados on its final voyage. This U.S. Navy fuel ship carried over 300 people and a large cargo. No distress signal was sent, and no wreckage has ever been found. Numerous theories exist, but none have been conclusively proven by evidence. Its disappearance remains the single greatest non-combat loss of life in naval history.