With 37km of racing to go in the Alps on Tuesday, some protestors from the Dernière Rènovation (Last Renovation, in English) set off flares and glued themselves to the road, while others were locked together by chains. The activists want the French government to insulate all homes to help reduce C02 emissions.
The protest forced the breakaway to be stopped and the race to be neutralised for almost 15 minutes while police forcefully removed them from the road in order for the action to get back underway.
While there was a positive reaction from many in the cycling world, others were less complementary about the disruption, with Philippe Gilbert, riding his last Tour before retirement, saying: "It's a bit disappointing because there are other ways to protest. I hope they will be punished in proportion to their stupidity."
Thibaut Cantent, one of the protestors from the Dernière Rènovation group who helped arranged Wednesday's demonstration, told Cycling Weekly that he and other climate activists are planning on repeating the act.
Although coy on exactly when, he said: "I think we will try [to do more], yes, just like at any other big event.
"The whole idea is that we will keep doing it until we're thrown in jail or heard by our government. As much as we can, and as much as resources will allow us, we'll continue to go to football games, highways and the Tour de France route, to where protests are possible.
"Sporting events today are one of the most accessible spaces for regular citizens to go [to and protest].
"The reality is we have very little power over factories and death machines that are operated around the world [because] they are highly monitored and guarded. Citizens are left with few options but to go and disrupt [places and events] where they can access. For us, regular citizens, the Tour de France is one of those places."
Cantent, who grew up in the French Alps, confirmed that the protesters who were removed from the road were held in police stations for 24 hours, and spent Tuesday night in police cells. They were released on Wednesday afternoon without charge.
"It was an action that we planned a couple of weeks ago," he said. "We have been disrupting major roads and sporting events in France for the last few months, and we gathered some supporters from the Dernière Rènovation group who wanted to take action.
"Most were from this area of France, but others came from different areas. We came to the Tour like any other spectator and took action. We wanted an area of high visibility and that's why we chose the long valley rode. It was designed in a way to stop the race."
Cycling Weekly approached ASO, the Tour's organiser, for a comment, but as of yet it has not responded.
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