Cheers mate. Part two will be a different subject as the posts are an introduction to some of histories more mysterious anomolies. I think Yonaguni and Dwarka are potentially evidence of the Worldwide 'great flood' as the construction dates are way back. Greco/Roman sites like Thonis-Heracleion however would be due to local flooding in the Mediterranean and besides they're not old enough. There are more being discovered especially in Asia where they have their own local flood and Atlantis type stories. They also have the oldest histories according to their own historians. Vast tracts of land were submerged very quickly across south and south east Asia so I'm sure many more will come to light in the coming years.
Good to see you back mate.