A trip of 8,000 miles, the longest ever to be undertaken by driverless vehicles, has begun.
Engineers will monitor the two vehicles as they travel from Italy to China as part of a test to examine the limits of future automotive technology.
As part of the trip, the two bright orange vehicles will tackle the traffic in Moscow, the summer heat of Siberia and the cold of the Gobi desert.
It is hoped they will arrive in Shanghai by the end of October.
Each vehicle will be accompanied with a lead van, and two technicians will sit inside the driverless cars to fix any problems as they go along.
"What we are trying to do is stress our systems and see if they can work in a real environment, with real weather, real traffic and crazy people who cross the road in front of you and a vehicle that cuts you off," said project leader Alberto Broggi.
The driverless vehicle takes cues from the lead van, but will have to respond to any ordinary obstacles or dangers. The two pairs alternate stretches along the route to China.
Governments have yet to produce rules of the road for driverless vehicles, so the team has obtained prior permission from all countries along the route to carry out the experiment. To protect themselves from liability, they are placing one of the technicians in the driver's seat, ready to assume the controls or hit an emergency shutdown button if necessary.
© Press Association 2010