An exclusive look inside Ground Truth, the secretive program to build the world's best accurate maps by Alexis C. Madrigal, enior editor at The Atlantic.

http://www.theatlantic.com/technology/archive/2012/09/how-google-builds-its-maps-and-what-it-means-for-the-future-of-everything/261913/

(Thank you Maning Sambale for sharing)