Sometime in the late 1960s I went with a school friend in his father's yellow-and-while Ford Anglia to a big race meeting at Silverstone.
After some heavy googling I think I have worked out which day it was: 27 April 1968.
That was the day of that year's Daily Express Trophy, which appears to be the sponsor's name for a race better known as the British Racing Drivers' Club International Trophy
I am sure I have the right race because I remember this programme from a long-vanished scrapbook of my childhood souvenirs.
It also places the meeting after my first football match and before I sang on the West End stage with Danny La Rue. Memory is is fallible, but that feels the right sequence.
The Daily Express Trophy featured some of the top Formula One drivers of the day and was won by Denny Hulme from New Zealand. (That Wikipedia page gives the date as 25 April, which confused me for a while, but I now think it is just an error).
A report from the MotorSport archive says the race was preceded by "a poignant silence in memory of the late Jim Clark".
And the race did indeed take place in the era when you expected some of the top Formula One drivers to die each season.
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Bruce McLaren, who finished second, died in a testing accident in June 1970. Piers Courage who finished fifth died the same month in a crash in the Dutch Grand Prix.
But it's not so surprising that it was another world when you are looking back 50 years.
By chance, the other day I saw a tweet from Transdiffusion Broadcasting System that showed that the race had been broadcast on ITV's World of Sport. It was so long ago that Dickie Davies was billed as Richard Davies.
And British Pathe and Bob Danvers-Walker were there too.