I would point out that history itself provides pretty solid evidence that Atlantis did not exist.

Consider the Greek culture of the time -- they adored stories. Stories were made into songs, told to children, legendary figures were painted and sculpted. Plays were written about them. Every important event in the lives of the cities (wars and all) were commemorated in poetry and more.

Now... many argue "but Troy was also considered to be a myth." Quite true... but there were sculptures of the heroes, art of the battles, plays (many that won awards), songs, and more. This is even true of stories that are simply popular myths.

So, if Atlantis WERE real, there would be a host of written material about it. There would be surviving artwork showing the Athenians defeating the Atlanteans. There would be murals depicting "Heroes of Athens killing Atlantean Hero-Ogre."

There are no artifacts, there are no mentions of kings and heroes (except in 20th century "channeled" material, and those names are clearly by people who (luckily) have no idea of linguistics or any language other than English).

Plato's notion that the Athenians fought a battle with Atlantis in around 10,000 BC is also clearly fiction. Athens may be old, but it's clearly not *that* old, and Greece certainly wasn't in the Bronze age in 10,000 BC.

There's no 'smoking gun.' The evidence for the reality of Atlantis is equal to the evidence for the reality of a teenaged wizard named Harry Potter who lives in England.