Almost thirty-five hundred years ago, several huge walls of water, the largest perhaps fifty meters (160 feet) tall, slammed into the islands of Thera and Crete in the Aegean Sea. These waves, called tsunamis, resulted from the explosion of Thera's largest volcano and, some scientists believe, may have supplied the factual basis for one of the world's most famous legends.

The legend of the lost continent of Atlantis is both familiar and romantic. According to the stories of the Greek philosopher Plato, the continent was larger than Africa and Asia combined and was home to people who ruled over Africa "as far as Egypt, and over Europe as far as Tuscany."1 Plato claims that on "one grievous day and night . . . the island of Atlantis . . . was swallowed up by the sea and vanished."2 Recent geological and archaeological findings...