I'm fascinated with all history, but if I had to pick only one nation, I would pick Atlantis.
We know very little about it, if it existed at all.
But if Plato's tale is right, then an advanced civilization ended 6,000 years before our own history began.
What is surprising is that Plato's date (~9600 BC) for the destruction of Atlantis coincides with 3 other dates from science:
* The abrupt end to the Younger Dryas, mini-Ice Age (~9620 BC),
* A moderately large volcanic eruption (9620.77 BC), and
* A sudden 2-meter drop in sea levels worldwide (~9620 BC).
Anthropologists have long remained puzzled how there were several incursions of more advanced paleolithic peoples which mysteriously arrived from "nowhere" into the realm of Western Europe and Northwest Africa. They could never accept the possibility that those mysterious "invaders" came from an island in the Atlantic a handful of miles off the coast.
The myths of elves who had magical powers, of dragons (snakes) which flew through the air and other magical things throughout the realm of prehistory, could all come from the refugees of Atlantis. Even the magic encountered by Odysseus when he circled the Tyrrhenian Sea could merely have been the children of Atlantis clinging to trinkets of, by then, ancient technology.
The golden dragons of the following myths could merely have been the same flying craft seen at different times over a period of hundreds or thousands of years:
* The Egyptian merchant prince,
* Cadmus and the founding of Thebes, Greece,
* Jason and the Argonauts (and Medea),
* Medea's escape from Athens, flying on a golden dragon, and
* Cecrops -- half snake, half man founder of Athens.
What geologists seem to forget is that most mountains are formed near tectonic plate boundaries, and that mountains formed in the ocean sometimes become islands. They forget, also, that the spot picked by Plato for his legendary island resides along the Africa-Eurasia tectonic plate boundary. And there is great evidence of plate boundary damage that may well indicate the formation and later destruction of Atlantis.