Google usually keep their data centers a secret. Many companies choose to hide them. For example, all our emails, YouTube videos, Google searches, Google Plus accounts and almost every Google product live in these data centers. Not only Google! Almost every website!
But recently, they have allowed us to walk through their North Carolina data center using street view. If you have never seen one, you must see it. While going through the tour, keep in mind that almost every thing you do in the web are powered by these huge facilities which contain thousands of servers. First watch the video and then jump to street view and walk into the big data center.