At least 11 people died and dozens more were injured as 300 vehicles slammed into each other on the A4 motorway near the wine-producing hill town of Soave at around 8am. Police and firemen used metal cutters and blow torches to reach the survivors stranded in vehicles that had jackknifed or dangled precariously from the motorway guard rails.
Several vehicles, including two lorries carrying pressurised gas, burst into flames, filling the gloomy morning air with a pale orange glow.
One truck driver called for help for nearly half an hour and eventually bled to death, according to witnesses unable to reach him because they were trapped in their own vehicles.
At the time of the accident visibility was down to no more than 20 yards, and although fog is a regular hazard in the Po valley area, many drivers - perhaps lulled by a false sense of familiarity with the stretch of road - were driving at 60 miles per hour or more.
One survivor, Alberto Filippi, said impact was so sudden that many drivers did not even have time to slam on their brakes. He survived only because he was inside a robust four-wheel drive. By his side lay the twisted remains of an Audi 80 and a Ford Escort whose three occupants all died.
Motorway pile-ups are a depressingly frequent occurrence in Italy, which otherwise suffers a relatively low death rate on its roads. In 1989, six people died on a different stretch of the same motorway, betwen Bergamo and Brescia.
"These days the A4 is a death-trap ... unable to support the particularly dense traffic flows in the Po valley because there is no other main road," said Senator Stefano Stefani, who represents Vicenza.
The worst accident on the country's motorways was also in 1989, on the A1, Italy's main motorway which runs from Milan in the North to Naples in the South, in which 13 people died.