On a night dripping with raw emotion in northern France, Wales went one better than their 1958 predecessors who reached the last eight of the World Cup.
They also did it the hard way after falling behind to Radja Nainggolan’s thunderous strike, with Ashley Williams, Hal Robson-Kanu and substitute Sam Vokes proving the goal-scoring heroes.
They will now meet Portugal in the semi-final in Lyon on Wednesday, but must do so without Ben Davies and Aaron Ramsey, absolutely outstanding again here, who collected their second cautions of the tournament.
It used to be asked who would provide Wales with goals if Gareth Bale – who will now come up against his Real Madrid team-mate Cristiano Ronaldo in Lyon – did not score.
But those questions are not being posed right now.
Skipper Williams claimed only his second goal in an eight-year Wales career, heading home Ramsey’s 31st-minute corner.
Then Robson-Kanu, a man without a club after leaving Reading this summer, scored a sensational individual goal 10 minutes after the break.
Robson-Kanu’s return to the side was a master stroke, preferred to Vokes after missing out in the last two games, as his extra mobility had troubled Belgium when Wales inflicted a 1-0 defeat on them in Euro qualifying in Cardiff just over a year ago.
That was the result, as well as two Brussels draws, which had persuaded Bale to describe Wales as Belgium’s bogey team in the build-up to this quarter-final.
And those words rang true five minutes from time when Vokes, who had only just been introduced, headed home Chris Gunter’s cross to confirm Wales as Britain’s first semi-finalists at a major tournament for 20 years.
This was the biggest night in Welsh football history since the 1958 World Cup quarter-final defeat to Brazil, the country having waited 58 years to return to a major tournament.
Hundreds of Wales fans were caught up in Eurotunnel delays before kick-off, but there did not look a spare seat at the Stade Pierre-Mauroy, with Belgians having travelled in their thousands from just across the border.
Wales manager Chris Coleman said: “It was amazing.
“Once we got through the group stage we knew we’d have a chance but playing Belgium, they are a top team.
“We knew we had to bring our A game and our players certainly did that.
“An incredible performance. We surprised Belgium.”
Wales midfielder Joe Allen added: “Words fail me. I never thought we’d be in this posituion. What an achievement.
“This means so much to everyone.
“We knew we’d score. Once we got level, everyone was confident we’d go on to win. We never give up.
“It will take something special to stop us.
“The emotions that the fans stir up in the lads, and vice-versa, that’s what football is all about.”