A German driver proved to be a little too trusting in following the directions of his car's satellite-guided navigation system.

Police say the system failed to note that the road he was driving along, near the eastern town of Potsdam came to an abrupt halt at a river ferry crossing.

The driver - expecting a bridge - kept going straight ahead in the dark, and the car ended up in the water.

Neither the driver nor his passenger were hurt, but river traffic was disrupted while the car was hauled out.

As a police spokesman put it, you can't always rely on technology.