426 BC Malian Gulf tsunami

In the summer of 426 BC, a powerful tsunami struck the coasts of the Malian and Euboean Gulfs in Greece. This event caused great damage to the areas along the shore. The ancient writer Thucydides studied what happened and decided that an earthquake under the sea was the reason for the tsunami. This was the first time anyone correctly linked a tsunami to an earthquake. Another writer, Herodotus, had explained an earlier tsunami near Potidaea as being because the god Poseidon was angry.

Ancient records

In the summer of 426 BC, a series of earthquakes caused a big wave, called a tsunami, in the Malian Gulf. This event changed the course of the Peloponnesian War, making the Spartans stop their plan to attack Attica. Strabo wrote that in Greece, parts of islands went under water, rivers moved, and towns were destroyed. The tsunami hit the coast in three places, reaching as far as three quarters of a mile inland. In one spot, the force of the water lifted a big ship called a trireme out of its dock and threw it over a city wall.

The writer Thucydides described what happened. He said the earthquakes caused the sea to pull back and then come rushing back in a huge wave. This wave flooded parts of towns, and some people couldn’t get to higher ground in time and were lost. Thucydides believed the earthquake was the reason for the tsunami because the strong shaking pushed the sea back, and then it rushed back with great force.