The Earth's Incredible Depth

We have a hard time visualizing how big the earth really is. We know intellectually that it's more or less a sphere that 24,000 miles around at the middle. From the surface to the sphere's center is 6731 kilometers (3958 miles). We've barely scratched the surface, literally, when we try to dig deep into it. How can we visualize that distance in a different way?   

Here's another mind blowing comparison from MetaBallStudios. They tale a core sample out of the earth the size of New York City and raise it up above the surface! The city itself is included for scale. This core blows past the altitude of the ISS in no time. You might want to keep your cursor over the pause button, because there are captions that describe what we are seeing, including terms you'll want to look up. Stay to the end, because there's a surprise sequence you won't want to miss. (via the Awesomer)