Merthyr Tydfil football heroes remembered in new film
It was the day a group of "working class valleys boys" beat a team of Italian football heavyweights.
In a result that could have been from the pages of a Roy of the Rovers comic, Merthyr Tydfil's part-timers defeated Serie A side Atalanta 2-1 in 1987.
While they lost the European Cup Winners Cup return leg, they had caught the attention of the world's media.
The players return to the club's Penydarren Park on Friday for the premiere of a film telling their story.
When ranking Welsh club football's greatest results, Cardiff City's 1971 victory against Real Madrid or Wrexham's 1984 triumph over Porto may be the more obvious choices for fans.
Even non-league Merthyr fan Matthew Davies, who made the film, admitted he had little knowledge of his team's moment of glory.
"Growing up (in the area), I didn't know much about it. It's only been in the last few years since I've started going down (to games) and finding out off fans," he said.
"There's not much footage online, but someone gave me archive footage and the whole story unravelled in front of me. It was quite incredible."
Mr Davies has now watched the match over 100 times and describes it as "a fantastic game" with the 10,000 fans creating an "absolutely unbelievable" atmosphere.
He also describes it as "ridiculous" that a bunch of electricians, labourers and accountants could defeat one of Italy's top sides.
The film, called The Martyrs of 87, uses interviews with the people involved - including chairman John Reddy, manager Lyn Jones and players Ceri Williams and Dai Webley.
Mr Davies said: "There were so many characters that were there - working class valleys boys.
"The international media went crazy and I think some fans in Italy still keep an eye on Merthyr Tydfil and Merthyr Tydfil fans still keep an eye on Atalanta.
"There is almost a subconscious partnership between the two now."
The film will be screened at Merthyr's Penydarren Park on Friday and then before the team's Southern League Premier Division game with Slough Town on Saturday.