>>9325670der humans like to build cities next to water, the ocean rose a shit ton during the glacial melt. the north american ice sheet run off, pulse water 1a, when it broke is thought to have been catastrophic, with the majority of the run off occuring in less than 100 years and raising sea levels worldwide by 40 meters.
there is a reason why the flood myth is a worldwide phenomenom, and stories of "atlantis" abound, because there were dozens of advanced cities for ancient times that were consumed and the people fleeing dispersed to continue nomadic lives, bringing the stories with them.