They came from as far away as Taiwan, Hawaii, South America and South Africa and they ranged from toothless toddlers to gray-haired grannies as they all shivered together in Copenhagen on Saturday. They spoke in countless different languages but the 30,000 activists marching  all had the same message: Act now on climate change.

Their hope is that the delegates to the Climate Conference — and more importantly the world leaders due in town later next week — will get that message.

“Bla Bla Bla. Act Now!” was the ubiquitous slogan on one popular placard. “There is no planet B“, “Change the politics, not the climate“, “Obama — get your head out of the Bush” and “Earth in Need. Delete Meat” were some of the other messages on posters and placards. My favourite was a simple hand-painted sign: “Make Copenhagen a name our children will remember“.

The atmosphere during the long walk was largely festive despite the finger-numbing chill and anyone who breathed deeply could not help but notice the distinctive scent of marijuana.

There were trucks filled with loudspeakers playing techno rhythms and other flatbeds carrying loud human speakers spouting witty slogans. But there was also a number of tense moments as the crowd moved slowly along a circuitous route through the southern districts of the city towards the Bella Centre, where the Climate Conference is taking place.

More than  six hundred were arrested after stones were hurled through the windows of a public building near the start of the rally while many booed, hissed and jeered loudly when the route passed in front of a McDonalds, which was protectively shut down before the march began, as well as a Kentucky Fried Chicken. Both had to be guarded by dozens of Danish riot place.

While few would blame McDonalds alone for climate change, the hamburger restaurant was evidently being held up as the symbol of America — and its past foot-dragging on climate change as well as its disproportionate 20 percent share of worldwide greenhouse gas emissions. 

Helena Christensen, a former Danish supermodel, drew loud cheers at a rally before the march started for urging Obama to be bold when he comes to town next week. “The United States must recognise the huge influence they have over what can happen with climate protection,” she said. “They will be very bad politicians if they don’t hear us now.” 

It was dark by the time we reached the heavily fortified Bella Center — about an hour ahead of schedule because most were eager to keep moving as it grew colder. There were torch lights and music but the finale was somewhat anti-climactic as we were forced to peer through the police lines and fences at the complex of buildings well off in the distance. Most were tired, cold and hungry — and soon headed for the nearest train station. But that station and the next were so packed that many of us ended walking back the 6 km into the city centre. 

“That was a lot better than I thought it was going to be,” said an elderly Danish woman doing what she could to stay warm by walking briskly back into town. “There were so many people of all ages and from all around the world. Let’s just hope those on the inside got the message.”