The Oera Linda Book, an alleged ancient manuscript that is generally considered to be a hoax, claims that at some time around 1600 BCE an earthquake closed off a strait that existed where the Suez Canal is now.
Soon after they had left the harbour they fell in with at least thirty ships coming from Tyre with women and children. They were on their way to Athens, but when they heard how things stood there they went with Geert. The sea-king of the Tyrians brought them altogether through the strait which at that time ran into the Red Sea (now re-established as the Suez Canal). At last they landed at the Punjab, called in our language the Five Rivers, because five rivers flow together to the sea. Here they settled, and called it Geertmania. The King of Tyre afterwards, seeing that all his best sailors were gone, sent all his ships with his wild soldiers to catch them, dead or alive. When they arrived at the strait, both the sea and the earth trembled. The land was upheaved so that all the water ran out of the strait, and the muddy shores were raised up like a rampart. This happened on account of the virtues of the Geertmen, as every one can plainly understand.
The Suez Canal article on wikipedia indicates that there is evidence of attempts to dig canals between the Nile River and the Red Sea at about that time but makes no mention of catastrophic geological events opening or closing a connection between the Mediterranean and Red seas.
Is there any evidence that such a passage existed during human history that was the result of natural events rather than human undertaking?
(*NASA satellite image of the Suez Canal is in the public domain and hosted by wikimedia commons.)