If you look at the photographs contained in the books of EvD there are some really strange, anomalous 'things' around the world.
Some will have rather prosaic explanations, others not so much....
My Mum was fascinated by the books of EvD and I started to read them in my early teens. We didn't know, at that time, that EvD lied about the things he had seen, where he had seen them and what he had been told about them. He name-checked Scientists, Geologists, Astronomers and Archaeologists but misrepresented their findings, theories and conclusions.
However, discounting the fabrications and hyperbole still left a satisfying number of puzzles to be mulled over. I honestly can't remember the names of all the books/authors I have read who have broadly the same opinions as EvD.
It is just one of the subjects that seemed to get more complicated as t'interweb became a breeding ground for all sorts of outlandish theories and conspiracy nuts.