5760 BC
5760 BC according to Stuart L. Harris was the probable date of the impact of an extraterrestrial intruder on the continental shelf of Texas that caused the sea to rise to a height of 1.9 km. generating a tsunami that spread in all directions.
In particular, Harris deals with its effects when it crossed the Atlantic causing devastation, not only in coastal regions but inland as far as the Rhine Valley. He offers a selection of data in support of that contention(a).