But that is just what scientists are planning to do deep below the Black Hills in South Dakota.

VOA: special.2009.07.21

Or it may still exist deep below the surface.

VOA: special.2009.12.30

These lay deep below the surface of the Earth.

VOA: special.2009.03.04

This is how she described what she could see from that house on a hill: "The far-off mountains in all their grandeur, and the deep valleys, and widely extended plains, and more than all, that little village below, containing only a very few white houses, but more than those young eyes had ever seen."

VOA: special.2010.06.27