Human civilizations go back pre recorded history with a noticable "absence" of knowledge about those before the last extinction level event around 13.000 yrs ago,we don't know and neither did Plato. What we do know is that some of the oldest remnants of those pre ELE civilizations are older then the first proto pyramids,older then Göbekli Tepe in Turkey but are advanced civilizations,just like the Sphinx is probably thousands of years older then the structures build by the earliest Egyptian dynasties. Most likely build around those ancient sites. Basically we don't know shyt past 14.000yrs ago.