Google is one step closer to achieving its goal of delivering a vehicle that carries passengers from point A to point B at the push of a button, effectively shouldering the burden of driving. This summer, prototype cars will roll off the test track and hit the roads of Mountain View, California, with safety drivers on board. That fleet has gone through rigorous testing, logging nearly a nearly a million autonomous road miles on the roads since the start of the project. More recently, the cars have self-driving about 10,000 miles a week. According to Google, it's the equivalent of about 75 years of typical American adult driving experience. The cars' top speed will be capped at 25 mph, and the safety drivers will avail themselves to a removable steering wheel, accelerator pedal and brake pedal in the event they have to take over.