Aea is a fair world with small continents and a huge conglomerat of islands. The game is focusing on a smaller section in the southern hemisphere, respectivly two continents and some island. The Aeternian empire is covering the southron one, while the northern one, closer to the equator and therefore much hotter and drier is split between the Afhan Territory and the Liberos Confederation.
Aea is quite an ordinary world, not too different from Earth, but there's one big difference: crystals. They exist in all forms and shapes on Aea, but they all have one thing in common: they are gateways to other places and forces, some on Aea, some on other worlds, some in radically different dimensions and universes.