5. Belgian Grand Prix - 1966
The old Spa-Francorchamps layout - where drivers sped through vast sections of the track lined by pine trees, farms and cows - was a treacherous proposition.
It was a perilous undertaking in the dry, let alone in the wet. And rain has often been the norm rather than the exception at Spa.
In 1966, drivers raced off the dry grid, scrambled through Raidillon and up the hill towards Les Combes only to find a wall of water at Burnenville, at the other end of the circuit.
So many cars went off on the opening lap that only seven drivers remained on course to complete the 28-lap event!
Among those who had been caught out by the atrocious conditions was Jackie Stewart. The Scot's BRM aquaplaned as he approached the Masta kink, hit a telegraph pole and then a woodcutter's cottage, finishing upside down in the basement of a farm building!
Graham Hill and Bob Bondurant, who had gone off at the same spot, discovered the stricken car, its driver swamped in fuel that threatened to ignite at any second.
With no marshals in sight, the pair worked furiously to extract Stewart from the wreck and carry him out of harm's way to a nearby barn.
The incident led to Sir Jackie's crusade to improve safety in Formula 1, and to fundamental organizational changes to the sport, whether it be circuit design or the installation of proper medical infrastructures at race tracks.
