Thousands of people across Britain have been commemorating the 60th anniversary of the Allied victory over Germany.
Prince Charles pays his respects at the Cenotaph
More than 40 million people had lost their lives by the time World War II ended in Europe on 8 May 1945.
Prince Charles marked VE Day by laying a wreath at the Cenotaph in London before meeting veterans in Hyde Park.
Then up to 15,000 people gathered in Trafalgar Square for a special televised BBC VE Day concert, presented by Eamonn Holmes and Natasha Kaplinsky.
At 2000 BST a Dakota DC3 flew at 1,500 feet over Big Ben, Whitehall and Trafalgar Square.
The flight by the plane, from the Battle of Britain Memorial Flight based at RAF Coningsby, Lincolnshire, signalled the start of the concert, headlined by Will Young and Katie Melua.
"Forces' sweetheart" Dame Vera Lynn made a guest appearance.
"These boys gave their lives and some came home badly injured and for some families life would never be the same," Dame Vera said.
"We should always remember, we should never forget and we should teach the children to remember."
The free event, called A Party to Remember, also screened footage of the original Trafalgar Square VE Day celebrations from 8 May 1945.
The concert, organised by the Royal British Legion, the BBC and London mayor Ken Livingstone, was shown live on giant screens in Birmingham, Liverpool, Manchester and Hull.
Prince Charles launched the first service of the day at the London Cenotaph.
It was followed by a march of around 2,300 servicemen through Hyde Park.
The prince was accompanied by the Duchess of Cornwall at the 81st annual parade and service of the Combined Cavalry Old Comrades Association at the park's Cavalry Memorial.
Neville Gillman, 87, from Chesham, Bucks, a former Desert Rat, who is now president of the Sharp Shooters' Yeomanry Association, said it was a "moving occasion".
"This lady came up to me and said 'I just want to take this opportunity to thank you'. What can you say. We just did what we had to do," he added.
In Scotland, First Minister Jack McConnell attended a church service in St Andrew's Cathedral, before laying a wreath on behalf of the Scottish people.
In Cardiff, veterans marked the day with a service at the cenotaph in Cathays Park and street parties were held in Birmingham, Liverpool and Manchester.
Four Spitfire planes also flew low across Duxford near Cambridge - which was a fighter base during World Wars I and II.
There was some disappointment among veterans at the London Cenotaph that the Queen and Tony Blair did not pay their respects at Whitehall.
Jack Bruce, 85, of Edmonton, north London, a former glider pilot who served in the D-Day landings and in Arnhem, was expecting a large-scale national celebration.
He said: "It's not good having something on such a small scale like this. If we don't have proper memorials the younger generation will never understand what we went through."
But a spokesman for the Royal British Legion said it was satisfied with the memorial plans and stressed that the Queen is due to lead further celebrations later in the year.
On Monday the Queen and the Duke of Edinburgh are due to visit Guernsey and Jersey to celebrate the 60th anniversary of the Channel Islands' liberation from Nazi occupation.
Ceremonies have been held across Europe to mark the anniversary.
US President George W Bush led commemorations at the US military cemetery in the Netherlands, where 8,000 servicemen are buried.
A service took place at Berlin Cathedral in Germany and French President Jacques Chirac attended a ceremony on the Champs-Elysees in Paris.
Around 265,000 British servicemen and women were killed in World War II, and tens of thousands of civilians died in the Blitz.