They hoped for 10,000, but in the end more than triple that number turned out on London's streets for the biggest demonstration since the beginning of the economic crisis.
The Put People First march yesterday was organised by a collaboration of more than 100 trade unions, church groups and charities including ActionAid, Save the Children and Friends of the Earth. The theme was "jobs, justice and climate" and the message was aimed at the world leaders who will be gathering for the G20 summit here this week.
The marchers, estimated at 35,000 by police, accompanied by brass bands and drummers and a colourful assortment of banners and flags, walked the four miles from Embankment to Hyde Park, where speeches from comedian Mark Thomas and environmental campaigner Tony Juniper, and music from the Kooks, made for a party-like atmosphere.
People came from all over the country and families with children in pushchairs were among those marching. Jyoti Fernandes, an organic farmer who travelled from Somerset with her four children, said: "We are here to remind people that we have to look after our land and look after our food."
A group of fewer than 200 anarchists joined the march and were kept isolated and surrounded by police. Chants of "Burn the bankers!" were the closest anyone came to any show of aggression despite a heavy police presence and a few buildings along the route, including the Ritz Hotel, boarding up their windows. As protesters passed the gates of Downing Street, there were chants and shouts of "Enjoy the overtime".