Do you remember when you were a kid, out playing with your friends, and someone decided to try to dig a hole to China? After digging for a while, you probably got bored, decided to do something else, and forgot all about the endeavor. If you did happen to remember it, you probably realized at some point that it is impossible to dig a hole to China. And even if you could dig a hole through the earth, chances are you wouldn’t end up in China.

So, you moved on to more important things in your life. But have you ever wondered about the biggest hole on the planet?

It happens to be the Mariana Trench. The Mariana Trench is a fifteen hundred-mile-long, forty-mile-wide trench in the Pacific Ocean, about one hundred twenty miles east of the Mariana Islands. The deepest parts of the trench are believed to be more than thirty-five thousand feet deep, but since it is so deep, getting accurate readings have been difficult. The Mariana Trench was formed by two tectonic plates colliding against each other, which also happened to form the Mariana Islands. Because there is very little life that far beneath the ocean, and the available technology makes a journey that deep expensive and difficult, few trips have been made.

Interestingly, film director James Cameron, who is best known for Titanic, made the descent to the bottom of the Mariana Trench in 2012. His was only the second manned dive to reach the bottom, making it to a depth of over thirty-five thousand feet.

So, the next time you see some kids planning to dig a hole to China, tell them to start in the Mariana Trench.