Recently discovered Göbekli Tepehttps://en.wikipedia.org/wiki/G%C3%B6bekli_Tepe, the oldest megalith structure, confirmed by radiocarbon tests to be more than 12.000 years old with massive stone pillars and 3d relief stone sculptures mostly still buried is still a mystery to science and some "scientists" still think hunter-gatherers built it with stone chisels.
The interesting thing is that a study based on the drawings on the structure correlated with Younger Dryas period might explain why nothing was found about the ancient civilization that built it.
https://phys.org/news/2017-04-ancient-stone-pillars-clues-co...
https://www.newscientist.com/article/2128512-ancient-carving...
So after all the Atlantis and the flood myth found in most cultures from around the world might be real.