Eight players died as a result of the Munich air disaster on 6 February 1958. Twenty-three people in total.
What Busby had built
Matt Busby became manager of Manchester United in 1945. Rather than buying established players, he developed them through the club's youth system, and then declined to sell them.
The result was a side whose average age in the mid fifties was around twenty-two. They won the First Division in 1955-56 by eleven points and retained it in 1956-57. Nobody expected the team to peak for years.
Europe
Busby insisted on entering the European Cup, over the objections of the Football League, which had successfully discouraged Chelsea from entering the previous season. United reached the semi-final in 1957 and were in the quarter-finals in 1958.
Munich
On 6 February 1958 the team was returning from Belgrade, having drawn 3-3 with Red Star and progressed on aggregate. The aircraft landed at Munich-Riem to refuel in snow.
Two take-off attempts were aborted for engine irregularities. On the third the aircraft failed to gain sufficient speed, overran the runway, and struck a house and a fuel truck.
The subsequent investigation initially blamed the captain, James Thain, for not de-icing the wings. It was eventually established, years later, that slush on the runway had prevented the aircraft reaching take-off speed. Thain was exonerated in 1968, a decade after the crash.
The dead
The players: Geoff Bent, Roger Byrne, Eddie Colman, Mark Jones, David Pegg, Tommy Taylor, Liam Whelan, and Duncan Edwards.
Also club secretary Walter Crickmer, coach Bert Whalley, trainer Tom Curry, eight journalists including the former England goalkeeper Frank Swift, a crew member, a travel agent, and a supporter.
Duncan Edwards
He was twenty-one, already twice a league champion and eighteen times an England international. He was extracted from the wreckage alive and survived fifteen days in Munich with multiple fractures and failing kidneys before dying on 21 February.
Bobby Charlton, who played alongside Pele, Best, Law and Eusebio, maintained for the rest of his life that Edwards was the finest player he ever saw.
Harry Gregg
The goalkeeper walked back into the burning aircraft more than once. He carried out a baby, then the child's pregnant mother, then returned for Busby and Jackie Blanchflower. He rejected the description of hero for the rest of his life.
What came after
Busby received the last rites twice in hospital in Munich and survived. He returned to management and rebuilt.
In 1968 Manchester United won the European Cup at Wembley. Bobby Charlton scored twice. Charlton and Bill Foulkes, both on the aircraft ten years earlier, were on the pitch.
The clock on the south side of Old Trafford is fixed at 3:04, the time of the crash. It has never been reset.
Why it goes on a wall
Because the team is remembered for what it did not become, and because the man who built it was read the last rites twice and went back to build another one.
Average age twenty-two.