The summer of Olympic and Paralympic sporting success will be etched on the memories of the public in the same way as the World Cup winning year of 1966, the Prime Minister said on Monday.
David Cameron hailed the London games as the "best ever" as he thanked gamesmakers at a reception in No 10 this morning.
The "golden summer" of sport had united the country and shown that Britain had the "confidence to deliver big things", he added.
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Cameron said Olympians and Paralympians "delighted and amazed" the nation and praised the Army, police and volunteers for helping the games to run smoothly and safely.
He said: "At the end of the most unbelievably successful Olympics and Paralympics, I just want to say what a golden summer of British sport and what a golden summer it has been for our country.
"I think it has given us a tremendous lift, I think it has brought the country together and I think it has given us memories that we will be talking about for years and generations to come.
Cameron met with gamesmakers at Downing Street
"I think that 2012 will be like 1966, something we'll talk about with our children and grandchildren, something that will continue to delight us long after this time has passed."
The Prime Minister said the "magical summer" had brought out the best in Britain for the world to see.
He said: "I think there is something else that we can take from this extraordinary period and that is for countries to succeed in this competitive and difficult world you need to have confidence that you can do big things and get them right, you need to have confidence that you can take on the best and beat the best, and I think the Olympic and Paralympics - we've absolutely done that as a country."
Cameron is sending a letter of thanks to every one of the thousands of volunteers who took part in London 2012, said his official spokesman.
The spokesman said: "One of the great success stories of the Olympics and Paralympics was the tens of thousands of people who have given up their time to support the Games. We want to thank them."
It comes ahead of a parade to celebrate Britain's Paralympic and Olympic athletes in London on Monday.
Athletes will travel on 21 open-top floats, grouped in alphabetical order by their sport.
The stars of the Olympics' Super Saturday will be on the first three floats.
The first will include Mo Farah, the Olympic 5,000 and 10,000m winner, followed by heptathlon gold medallist Jessica Ennis, with long jump champion Greg Rutherford in the third float.
Team GB's cycling stars Sir Chris Hoy, Jason Kenny, Laura Trott and Victoria Pendleton will be in float seven, followed by double equestrian gold-medal winner Charlotte Dujardin, rowing champion Katherine Grainger, Ben Ainslie, Britain's most successful Olympic sailor, and triathlon gold medallist Alistair Brownlee.
Paralympians Hannah Cockcroft, Jody Cundy, Sophie Christiansen and Jonnie Peacock will also take part in the parade.