London 2012 parade: One last amazing day in a city that doesn't want its party to end

Hundreds of thousands turn out to celebrate Britain's Olympic and Paralympic heroes

The greatest show on earth, as it has become customary to call it, finally came to an end with the grandest lap of honour. Hundreds of thousands of people filled London's streets, 30 deep in many places, on a windy, occasionally drizzly afternoon, for one last look at their Olympic heroes.

More than 800 athletes, very nearly every Olympic and Paralympic competitor, filled 21 floats that left from Mansion House in the City of London at lunchtime, and slowly made their way through the City, past St Paul's Cathedral and down the Strand. Crowds poured into every conceivable inch of pavement space, packing the entrance to the Savoy Hotel. Trafalgar Square, so often the centre piece of such occasions, appeared as packed as it could conceivably be. "We were here in 2005, when we won the bid," said Christine Horton, who was there with her daughter, Grace. "Well I was, she wasn't born. And now we're here again. I don't think anyone knew in 2005 it'd be like this. It's magical."

When Mo Farah arrived on the first of the floats, and placed his hands on his head to form what is now known as the "Mobot", Christine, Grace, and everyone else, went more than a little bit crazy.

Lining The Mall as the parade came to its final stop outside Buckingham Palace were 1,500 Games Ambassadors, in their pink and purple uniforms, hundreds of whom signed away their summers to not even catch a glimpse of any sporting action, instead working at Heathrow and Gatwick airports.

The floats were led in by grinning police officers on horseback, Paralympic Games accreditations still hanging round their necks, who waved and joked with the crowd – a scene representative of the unique mood in the capital for the past six weeks.

Ellie Simmonds waved at the crowds, as did Sarah Storey. Several of the athletes on the floats held up handmade signs reading "No, Thank YOU" and "You Made The Games". The Brownlee brothers hung off the back of their float to pose for photographs, and Katherine Grainger, the 36-year-old rower who won silver in Sydney, Athens and Beijing, and finally gold in London, was trying but by and large failing to hold back tears.

With the full Olympic and Paralympic teams assembled on steps at the Queen Victoria Memorial, in front of an invited crowd of police officers, service personnel, G4S guards (thousands of whom have done a very good job this summer), Locog and British Olympic Association staff, David Cameron said thanks to everyone involved in the London Games. "Thank you to the athletes, you've given us a gold summer for British sport and you've made us all so proud. The whole country salutes your brilliance," he said.

"And thank you to all those who made this possible, Seb Coe and his team, the police who kept us safe and to our service men and women who stepped up so magnificently, you proved again you are the best in the world. And to all of you who turned London into a city of smiling faces, you turned this is into the greatest Games ever.

"This is the great British summer, that will be remembered for many years to come. Let the spirit that brought this country together, let that spirit live on for generations to come."

The last word fell to the Mayor, Boris Johnson, who as has so often been the case this summer, rather stole the show. The crowds even chanted "Boris! Boris!" before he began. "You showed every child in this country that success is not just about talent and luck but about grit and guts and hard work and coming back, and you showed fantastic grace in victory and amazing courage in defeat," he said. "And speaking as a spectator, you produced such paroxysms of tears and joy on the sofas of Britain that you probably not only inspired a generation but helped to create one as well. Above all you brought home the truth about us and about this country – that when we put our minds to it there is no limit to what Britain can achieve."

How long the Olympic spirit will stick around for is impossible to know, but while athletes were parading through the streets, figures released by the Local Government Association showed that in its survey of more than 400 leisure facilities, crowds are already arriving in bigger numbers at public swimming pools, gymnastics classes and cycling venues. It is an auspicious start.

Many athletes were quick to point out that the parade was about the crowd, not about them, but they seemed to enjoy themselves anyway. "It is crazy, the amount of support that is there, I really didn't expect this number of people to turn out," said Tom Daly, the 18-year-old diving bronze medallist. Asked if he'd had doubts about what many have seen as giving up his teenage years, he said: "This is what I have always dreamed of, winning an Olympic medal. All the hard work, all the sacrifice, it has been worth it. Look at this," he said, gesturing towards the crowds.

Ellie Simmonds, who won four Paralympics medals, said: "It was great to celebrate and be part of the Closing Ceremony last night; it was unbelievable. It is amazing the support they gave us during the Olympic and Paralympic Games. To celebrate with the public here, the ones who helped us have the home advantage."

After a flypast from the Firefly, the gold-painted plane that brought the flame from Athens four months ago, with the words "Thank You" newly painted on the undercarriage, the Red Arrows did their thing. As 800 ecstatic athletes celebrated in their Union flag tracksuits, a couple of red, white and blue ticker-tape cannons went off, and that was it, the end.

Views from the streets: the people's verdict

Lucio Buffone, 37 London, freelancer: "I came along today because it's been such a fun summer in London and I had to give it closure. It was sad in that respect. What was amazing was how many medals there were. It was insane. It was a good opportunity to say thank you for the sheer joy and excitement of the summer."

Sharon Eldred, 38, Archway, nurse: "My favourite bit was the atmosphere and the crowd and everyone being really friendly. I didn't realise that the volunteers were going to be part of the parade and seeing them at the end was really good. It was a nice thank you to them. I think that some of the biggest cheers were reserved for them."

Micheline McAteer, 44, Hornsey, aromatherapist: "The atmosphere was indescribable. I really hope that we can keep it going. We've been caught up in the emotion and excitement of the day but I hope that we can maintain it and put it to good use. This has definitely changed our attitudes towards disabled people. I've worked with people with learning disabilities for more than 20 years and I think it's amazing what England has done to bring disabled athletes to the forefront and for people to look at them as athletes and not as disabled people. The British public deserves credit for that."

Robert, 35, London, animator: "It was a case of putting some real personal connection to what can just be TV otherwise. I've never been to a victory parade before but I instinctively knew that I had to be here. My one complaint is that there were signs with the gold stamps for the big stars to hold, which I thought was a bit tacky. I think that there's already an inclination to focus on the celebrities which we create ourselves and I don't think that needs reinforcing".

Harry Cocking, 7, Lincolnshire: "I've been here a long time, we had to get up early. We saw Claire Cashmore and Mo Farah. It was very busy and very noisy when everyone was going past."

Archie Cocking, 5, Lincolnshire: "I liked the Olympics. I'd give it one million out of one million."

Jocelyn Jenner, 71, Pitlochry, retired: "I'm very proud to be down here from Scotland. It's absolutely amazing; from start to finish it has been run superbly. The whole event is absolutely wonderful, the Olympic Park is wonderful, the stadium; it's just sheer magic. Today has just been a wonderful celebration."

Views from the floats

"We never knew how many would turn up. But my word, we could never have expected this" - Kath Grainger, Rowing gold medallist

"I am so proud of the British public to come out and watch Paralympic sport and embrace it" - Lee Pearson, Dressage star with 10 Paralympic gold medals

"It's nuts, I've never seen anything like it. I'm proud. The whole nation has done a fantastic job" - Ben Ainslie, Four-times gold medal winning sailor

"I didn't think it was possible to see so many supporters. I just want to say thank you" - Sir Chris Hoy, Six-times Olympic track cycling champion