The odds of all of the men - Portsmouth Grammar School's rugby team - being still alive was worked out at 256,000 to one.
Dr Phil White, who had travelled from Vancouver, Canada, told The Daily Telegraph: "It was fabulous to see all the boys again. I hadn't seen about 95 per cent of them for 50 years.
"Obviously, everyone has aged but their personalities and characters are all still the same."
Dick Churm, now living in Brittany, France, added: "I haven't seen any of these boys for 50 years.
"It was quite unbelievable to see them all again. We always had a lot of fun together."
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