The sea retreated for an hour before it destroyed a city
In short: In AD 365, the Mediterranean Sea didn't just rise; it vanished. For nearly sixty minutes, the seabed of Alexandria lay exposed to the sun as ships sat stranded in the mud. Crowds walked onto the wet sand to gather fish, unaware that the ocean was preparing a catastrophic return.
The tragedy began roughly an hour before sunrise on July 21, AD 365. A massive earthquake struck off the island of Crete, more than 600 kilometers away from Alexandria. The seismic shift was so violent that it lifted the western end of Crete nine meters out of the sea. This movement sent a tsunami racing across the Mediterranean toward the Nile Delta, where it struck one of the ancient world's greatest ports. When the wave reached Alexandria, it first caused the water to recede with unprecedented speed and distance. The harbor floor was revealed, leaving ships tilted in the silt. In a display of human behavior that remains a subject of study, many people walked toward the shoreline to collect stranded fish rather than fleeing inland.
About an hour later, the sea returned with immense force, carrying vessels over quays and onto the rooftops of houses, leveling innumerable buildings. Historical records from the Roman historian Ammianus Marcellinus suggest that many thousands—some accounts estimate as many as 50,000—people drowned in the event. Perhaps most striking is the fact that the warning signs were already documented. Eight hundred years earlier, the Athenian historian Thucydides had recorded a similar phenomenon caused by an earthquake, explicitly noting that those who failed to reach higher ground were lost. Despite centuries of studying these records, Alexandria continued to mark the anniversary with lamps and prayers rather than implementing the life-saving rules written in their own history.
Archaeological evidence supports this historical narrative. Excavations conducted between 2007 and 2020 uncovered a monumental public building's foundation dated between 326–424 AD, which researchers believe was exposed by the tsunami's power. While some seismologists have debated the full extent of the destruction, geological studies confirm that the Egyptian coast remains highly vulnerable to such recurring seismic activity.
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Sources
- Summary by Intellect · source: THE ALEXANDRIA TSUNAMI TRAGEDY: The Wave That Left Ships on the Rooftops | Full Documentary
- Also: ARCHAEOLOGICAL EVIDENCE OF THE TSUNAMI OF 365 AD IN ALEXANDRIA-EGYPT
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