I want this to be the Inner Earth. Well, inner from our perspective. It would work out that the people of Inner Earth would just see it that *we were the inner surface*. So you go through the right point in the ground of Antarctica, and you find yourself moving over a lip that leads to the 'inner surface' of the globe. But just as you cross that point, perspective inverts so that it's just like you're on another globe. On that 'inner' globe surface there are whole new continents and oceans. The ancient, highly advanced civilizations that constructed the first pyramids never went extinct. They have always lived on Inner Earth. Atlantis didn't sink. It's on the surface of Inner Earth. There is no iron-nickel core in the Earth, you goofballs. It has always been a highly advanced spacecraft which produces its own oil as fuel and self-locates at the optimum orbits around mid-life, medium-sized star systems. Geeze. It's like day one at the academy trying to talk to you guys. By the way, Hitler has a message for you: "Guten Tag! Ich wünschte, du wärst hier!"