A period of silence for the victims of the Munich air disaster was observed before England's friendly against Switzerland at Wembley.
Earlier, a minute's silence took place at Old Trafford at 1504 GMT, timed to coincide with the moment of the crash 50 years ago when 23 peope were killed.
There was a simultaneous service at the crash site in Germany.
A period of silence also took place at the home games involving Northern Ireland and Wales.
Eight Manchester United players were killed in the crash and the service at Old Trafford saw Sir Bobby Charlton - one of the survivors - present.
A thousand people were also inside Old Trafford's Manchester Suite for the memorial service, with many more outside on Sir Matt Busby Way where a clock commemorates the events of 6 February, 1958.
The ceremony was led by United's club chaplain the Reverend John Boyers and included speeches by Charlton and Harry Gregg as well as a message from Prince Charles.
"It wasn't just Manchester United, it was the city of Manchester and the world of football that was affected"
As well as the service in Manchester, at which Charlton and Gregg were joined by fellow survivors Albert Scanlon, Bill Foulkes and Kenny Morgans, there was another ceremony in Munich.
The three sons of owner Malcolm Glazer were also present.
Charlton paid tribute to those that lost their lives, saying: "The team that was decimated in Munich would, I think, have been the first British team to win the European Cup."
At 1330 GMT, an English-speaking Catholic priest conducted a religious ceremony at the crash site in Trudering, attended by a group of 400 fans, who left scarves and hung flags at the site.
The names of the dead were read out, along with the lyrics to The Flowers of Manchester, a song penned after the disaster as a tribute to the dead.
Bayern Munich chairman Karl Heinz Rummenigge was among those to address the mourners.
"February 6, 1958 was a black day in the history of Manchester United, but also for football in general," Rummenigge said.
"I'm proud to be a fan of Manchester United. People in England say God save the Queen. Today, I say God save Manchester United."
On a day of commemoration at Old Trafford, the centrepiece was the unveiling at 1645 GMT of a free, permanent exhibition of the Busby Babes in the South Stand tunnel, now renamed the Munich Tunnel.
The exhibition was unveiled by Roger Bryne Jnr, whose father, Roger Byrne, died in the crash, and Manchester United chief executive David Gill.
England and United defender Rio Ferdinand says he hopes supporters at Wembley will remain silent in tribute to the people who died.
"I'm sure the fans will respect it - it's a poignant moment and we've got fantastic fans in this country," said Ferdinand.
"It's not just about Manchester United, it's about English football too."
Speaking to BBC Radio 5 Live on Wednesday, Gill said: "That day 50 years ago is still very clear in the minds of the family and friends of those who died."
On Sunday, there will be another minute's silence prior to United's home Premier League game against Manchester City.
606: DEBATE
Former City goalkeeper Frank Swift - then working as a journalist - also died in the crash and Gill says he is confident the City fans will fall silent in tribute.
"We've been working closely with City and discussed it with them. Frank Swift was one of their greatest goalkeepers and we've talked to them about the plans for the day," said Gill.
"We're working to ensure they remember that it wasn't just Manchester United, it was the city of Manchester that was affected and it was the world of football that was affected.
"We hope and believe that the minute's silence will be observed appropriately."
United players will wear a 1950s-style kit, free from sponsorship and numbered one to 11, while City will also wear a special strip.
~RS~q~RS~~RS~z~RS~53~RS~)