Picnic for peace

The day started - appropriately enough - at Speaker's Corner, long the home of a broad church of dissenters agreeing to disagree.

But Saturday was a day of agreement, with a diverse crowd of about 20,000 people united in opposition to air strikes on Afghanistan.

Alison David, 28, a singer-songwriter and mother-to-be from Brighton, told BBC News Online she was protesting because of the loss of innocent lives in the strikes.

"I only found out about this an hour ago and came straight here. My friend sent me a text message and I forwarded it to everyone I know."

Mother-to-be Alison David: No retaliation

"I do not believe that retaliation is the best way to react," she said.

Ten-year-old Amy Poole, from York, agreed, saying: "In one of our school assemblies it said that retaliation is wrong and that is what the United States is doing."

Ascending the escalator at Marble Arch tube station, the air was already buzzing with informed and impassioned discussion.

And if Blair, Bush and Bin Laden's ears had not been otherwise engaged, they would have been burning.

Amy Poole: Retaliation is wrong

Business student Zyad Hassen, 21, of High Wycombe, told BBC News Online: "I want to demonstrate because I do not agree with what the UK and the USA are doing with the war.

"I live in this country and I do not agree with what the country is doing. I want the war stopped."

Passing through ticket barriers kept open to allow protesters to flow through smoothly, the next leg of the trip to Trafalgar Square involved running the gauntlet of paper-sellers and pamphleteers lining the subway to Hyde Park.

Carnival outfits combine with more sombre garb

Once out in the brilliant sunshine carnival outfits combined with more sombre garb as whistle blowers rubbed shoulders with women wearing veils.

Colourful homemade banners adorned with flowers and cardboard cut-out hearts jostled with stark printed placards stating: "Socialist Worker. Stop This Bloody War. Fight US/UK imperialism".

Starker still were the pictures said to be of some of the first wounded victims of the air strikes, staring silently up from the scores of leaflets already littering the floor.

Sarah Shah: Against what leaders are doing

Islamic studies student Sarah Shah, 24, of Birmingham told BBC News Online: "I think it is horrendous that thousands of innocent people died in the US - but it is equally unjust that this is being used to kill thousands more.

"I am voicing my opinion against what our leaders are doing.

"It is their duty to take notice of what their people want."

Helicopters hovered overhead as the procession snaked through London.

But down on the ground the city's well-represented Metropolitan police force met the anarchist Wombles - White Overall Movement Building Liberation through Effective Struggle - with cheery waves.

Drum-onstartion: March had carnival atmosphere

Marchers chanted, sung, whistled and drummed their way towards the square.

But as the different groups and individuals filed past, refrains changed from: "We want peace!" to "Islam means peace!" and then "USA - terrorists!"

Those who oppose military action may be in the minority - but judging by Saturday's demonstration they come from a broad cross section of society and span many of Britain's racial and cultural divides.

Abdul Rashid, 75, a retired company director from East Ham said: "I am against the war because war is not good for anyone."