The three young boys were playing peacefully in the garden in front of a house in Aesch, south of Basel, when they suddenly had an idea, Blick newspaper reported.
The boys stole the key to the truck from a post box before the 6-year-old got behind the wheel and drove with his two passengers, aged five and seven, to Reinach some five kilometres to the north.
Their impromptu adventure came to an end when the pint-sized driver tried to turn the vehicle and instead drove backwards into a garden fence.
As local residents went to check what was happening, they saw the three budding truckers in the cab and notified the police.
The 6-year-old's mother had not noticed that the three youngsters had disappeared.
“Suddenly the police arrived at the door with the boys. It was a huge shock,” she told Blick.
The woman could hardly believe that her little boy had driven so far without having an accident.
“The police told me that he stopped at a red light and drove correctly around a roundabout,” she said.
She added that he had never before sat behind a steering wheel, although he did own a selection of toy cars.