The 1970 Mexican Grand Prix, held on this day forty-seven years ago, drew a huge crowd to the Autodromo Hermanos Rodriguez.
Attendance figures were estimated at 200,000, but pressured for space the fans pulled down much of the safety fencing to sit on the track's embankments.
Jackie Stewart made a plea to the crowd, asking people to move back, but it was all in vain. Fearing a riot if the race did not get underway, organisers told the drivers to get on with it, which they did.
Ferrari won the race by the way, with Jacky Ickx leading home team mate Clay Regazzoni.