When you were a kid, did you ever dig a hole just to see how deep you could go?
I did, and even though I was probably only a few feet down, I could “sense” the temperature getting warmer in the hole as I approached the center of the Earth… Little did I know that I was still very, very far from the core.
Other people have obviously been more successful than my sandbox digs – achieving depths of around the 40 thousand feet. The infographic below illustrates some of the world’s deepest holes along with a quick fact for each of them.
Image Source: http://www.geoconsiteinvestigations.com/