Activists have been gathering in Glasgow to urge world leaders to turn words into action on the climate crisis, ahead of the crucial COP26 meeting over the future of the planet.Many of them have marched for tens or even thousands of kilometres to reach the Scottish city, where the UN climate conference gets underway on Sunday and will run until the November 12.Swedish climate activist Greta Thunberg was met by a media scrum as she arrived at the railway station early on Saturday evening. Police officers had to escort her through the crowds and streets of the city.The 18-year-old was among several activists coming on a special COP26 train from London. There, the day before, the instigator of the “Fridays for Future” movement joined a campaign by young environmentalists against the role of financial institutions in the climate crisis.Other protesters have come from countries such as Belgium, Spain and Sweden. Demonstrators were led by members of the Extinction Rebellion direct action group, which has brought cities around the world to a standstill and has vowed to do the same in Glasgow.Some protesters held banners reading “The era of injustice is over climate justice now” and “Climate refugees welcome”.“We are waiting for more ambitious measures, for our political leaders to be aware of the urgency of the situation,” Dirk van Esbroeck, a Belgian pensioner, told AFP. “Because our children, our grandchildren risk living in a much more complicated world, which is going to suffer serious climate disruptions.”He and about 20 other members of a group called “Grandparents for the Climate” had travelled by train from Belgium to Edinburgh, before walking the last 75 kilometres to Glasgow.“There is still a long way to go between declarations and action,” added the 68-year-old, who has five children and 12 grandchildren.More than a hundred leaders, including the American Joe Biden, the French Emmanuel Macron or the Indian Narendra Modi are expected at the summit. Thousands of climate activists from around the world will also make the trip. Becky Stokes, a 31-year-old translator who walked from Spain, said she and fellow protesters were there to demand “concrete measures” to help the world’s southern countries. COP26 represents a “last chance”, she told AFP.”There have already been 25 COPs and the climate situation has never been so bad,” said Maciej Walczuk, a 19-year-old student. He is hoping for a “different” conference this time around, which “commits to action to save lives”.Scottish police say some 10,000 officers from across the UK will be deployed every day during COP26, the largest law enforcement operation Scotland has ever seen.