Colorado for one:
http://www.dailymail.co.uk/sciencetech/article-3870790/Beer-run-Self-driving-truck-goes-120-plus-miles-delivery.html
"A human drove the truck onto the highway..."
Driving on the interstate is the EASIEST part of this engineering problem.
Let me repeat the question:
Example please. No...not some test where there is a driver in the front seat who takes over when the car is confused...an honest to goodness bona fide example of a vehicle that can traverse city streets with no input from a driver. Where IS this happening?