Answer:
Well, if you know nothing about science Than who's to say that there's not a huge compase at the center of the earth! We have directions like North, East, West, and South as our main directions. If you know nothing about science then you wouldn't actually know what gives us the direction. I would say a huge compass.
There could be A steel ball in the center of Earth No one was been able to dig to the center that's because they can't dig through steel!
A built-in Heater! It's always a lot hotter the closer you get!