Google Earth has been downloaded more than one billion times since it was first introduced in 2005, said Brian McClendon, VP of Engineering, Google Earth and Maps, writing in a blog post. “When we founded Keyhole, back in 2001, we never imagined our geospatial technology would be used by people in so many unexpected ways,” he adds. In case you are wondering what Keyhole is, it was the Mountain View-based digital mapping company that Google acquired in 2004. Keyhole’s technology combined a multi-terabyte database of mapping information and images collected from satellites and airplanes, and it went on to form the backbone of Google Earth.

Just how much is one billion? Well, one billion hours ago we were living in the Stone Age…