ST. IVES, England — Claudia Benzies walked 84 miles to protest at the Group of Seven summit on Britain's far-west coast.

The 69-year-old set off on June 5 from Plymouth, England, and camped in fields along the way. “I can show you all the blisters,” she said, laughing.

British Prime Minister Boris Johnson, by contrast, opened himself up to criticism by taking a private jet to the three-day summit, which he had emphasized would be environmentally focused and carbon-neutral.

“I’ll be asking my fellow leaders to rise to the challenge of beating the pandemic and building back better, fairer and greener,” he tweeted, with an image of himself stepping out of the plane.

Demonstrators who have congregated here say that is emblematic of how government leaders hit the right notes when they talk about the need to address climate change but ultimately fall short of their commitments.

Asked what she would tell G-7 leaders if she had the chance, Benzies said, “I’d show them my granddaughter’s sock,” she said, holding a tiny pink sock in her hand. “I found it in my backpack and suddenly thought, I’m looking out for her and future generations.”

The leaders of Britain, the United States, France, Germany, Canada, Italy, Japan and the European Union do have climate change high on their summit agenda, along with coronavirus vaccines and corporate taxes. Queen Elizabeth II and other senior royals will be putting on a charm offensive at a reception Friday evening at the Eden Project, a tourist attraction featuring domed biomes.

Johnson, as summit host, is seeking to get financial commitments from the leaders of wealthy nations to help poorer countries reduce their carbon emissions and deal with the impacts of climate change. And the British government has pledged to offset all the emissions from the summit, including the jet fuel that got people here.

Still, demonstrators say they want to see more ambition — from the G-7 and from the COP26 summit this fall in Glasgow.

Protesters gathered in Cornwall, England, to demand action on climate outside the Group of Seven summit on June 11. (Karla Adam/The Washington Post)

On Friday, Extinction Rebellion, a climate activist group, noisily marched through St. Ives, a seaside town, and “sounded the alarm for climate justice,” with horns, drums, rattles and a samba band. After the jamboree snaked through town, a small delegation — accompanied by about 80 police officers — hand-delivered letters to the gates of Tregenna Castle, where the leaders are staying.

There is a heavy security presence, with officers and security guards stationed every 10 feet or so along the roads surrounding the hotel. Several streets are blocked off with fences, forming a “ring of steel.” A massive frigate in St. Ives Bay is another reminder that the G-7 is in town.

“All eyes are on the U.K., and we want to highlight the responsibility that world leaders have this year to make the radical change that’s needed,” said Alanna Byrne, a spokeswoman for Extinction Rebellion. She said British leaders talk a good game on climate but have not sufficiently backed up the rhetoric.

“It’s green-washing,” she said. “They are adopting the language of climate change, but in reality it’s just words, no action. They are still funding fossil-fuel projects and devastating biodiversity in the U.K. in a massive way.”

President Biden has heard similar complaints from activists in the United States who fear he is backing away from more-ambitious climate goals. Former vice president Al Gore called Biden to voice his concern last month.

Abbey Hubbucks, 24, a waitress and dressmaker who joined the protest Friday, said that Johnson flying to a conference to talk about climate was “ridiculous, but equally, everyone’s a hypocrite — nobody’s perfect.”

“In an ideal world, Boris would have cycled here. I would have cycled here,” Hubbucks said. “But that’s why we need real solutions, real green alternatives to flying.”

There were several protest events planned over the next few days, with organizers hoping to highlight a range of issues, including a piece of legislation going through Parliament that its critics say will limit the abilities of these very protesters. It has prompted demonstrations across the nation to “kill the bill.”

The G-7 and other similar summits have long been a focus for protesters. But this is the first time organizers have planned gatherings during a pandemic. Resist G7, a coalition group, encouraged its supporters to take lateral flow tests, follow social distancing rules and wear masks. Organizers are also encouraging supporters to ignore the police’s recommended protest sites, which are not in the towns the leaders are staying or meeting in.

While they will inevitably be colorful, the protests planned over the three days were expected to be far smaller than those that met the last U.S. president. When Donald Trump came for an official state visit two years ago, tens of thousands of protesters spilled onto the streets of London. Some flew a giant diaper-clad “Trump Baby” balloon high above Parliament Square.

There are visually arresting props this year, too.

One of the most striking is a sculpture of the G-7 leaders that is modeled on Mount Rushmore. Dubbed “Mount Recyclemore,” the imposing artwork hopes to showcase the damage from the disposal of electronics. The creators of the installation say the G-7 nations contribute almost 15.9 million tons of e-waste a year, with the United States the worst offender.

Joe Rush, a sculptor who created the artwork, told the BBC that it was built across the water from the summit location in hopes that the leaders would see it when flying in. “We have this looking at them and hopefully we’re going to prick their conscience and make them realize they’re all together in this waste business,” he said.

“The key message is ‘talk to each other’ and let’s sort this mess out,” he said.