The ancient Greek historian Herodotus included many reports in his recounting of history that have not been able to be confirmed. Now one, at least, appears to have been substantiated by modern science. The BBC reports:
German geologists believe a tsunami recorded by the ancient historian Herodotus did indeed protect a Greek village from Persian invaders.
They say they have found evidence in northern Greece that the event in 479 BC saved the village of Potidaea.
Herodotus recorded that huge waves had killed hundreds of Persian soldiers during the siege of the village.
. . .
Sediment on the northern Greek peninsula where Potidaea and the modern town of Nea Poteidaia are located shows signs of massive marine events, such as large waves, the Aachen study found.
Excavations in the suburbs of the nearby ancient city of Mende uncovered sea shells likely to have been lifted from the ocean bed and tossed about during a tsunami.
There's more at the link.
Herodotus wrote about the incident (The Histories, 8.129.1-2):
But when Artabazus had besieged Potidaea for three months, there was a great ebb-tide in the sea which lasted for a long while, and when the foreigners saw that the sea was turned to a marsh, they prepared to pass over it into Pallene. When they had made their way over two-fifths of it, however, and three yet remained to cross before they could be in Pallene, there came a great flood-tide, higher, as the people of the place say, than any one of the many that had been before. Some of them who did not know how to swim were drowned, and those who knew were slain by the Potidaeans, who came among them in boats.
It's fascinating to have so ancient an historical account at least partly verified by modern science. I've always enjoyed Herodotus' stories, and to have one of them brought to life in this way is pretty amazing.