In Cologne today, a 60 year old man drove his car, at speed, off a ramp and into the Rhine. His on board satnav (navigation device for you colonials) told him to. Nobody had told the makers that the road ended in the river. The man managed to save himself but the car sank to the bottom.
It gets better.
The authorities got the divers out to recover the car. An underwater locating device told them exactly where it was.
They brought the car up only to find that it was the wrong one. The one they salvaged had a body in it. Car and body had disappeared four years ago.
Divers went back down and this time came up with the right car.
If you need to get rid of somebody or something bulky the river authorities in Cologne can show you a handy spot.