What is inside the Earth?
Earth's Secret Layers
What is inside the Earth?
You're standing on something absolutely wild right now. Under your feet — beneath the sidewalk, the soil, the basement, the bedrock — there's an entire hidden world stretching thousands of miles down. It's not empty down there. Not even close.
The first layer is the crust — the thin rocky shell we live on. It's like the skin of an apple, except the apple is 8,000 miles wide and the skin is only about 20 miles thick under your feet. (Under the ocean it's even thinner, just 3 to 5 miles.) All the mountains, all the caves, all the deepest mines humans have ever dug — we've never gotten through the crust. We're still scratching the surface.
