Fifty years ago, as France exploded in mass protests, words scrawled on the walls of the Sorbonne summed up the revolutionary zeal of the time: “Run free, comrade, we’ve left the old world behind!”. Sexual liberation, artistic creativity and anti-capitalism were the order of the day. For those who were there, it was an unforgettable time. Here: A wounded student is transported by first-aid workers during riots on the Boulevard Saint-Michel, Paris, France on May 6, 1968. (Photo by Gökşin Sipahioğlu/SIPA Press)

A municipal worker sits on a bench, next to a statue, in Nizhny Novgorod, Russia, during the 2018 soccer World Cup, Thursday, June 28, 2018. Nizhny Novgorod was a “closed city” during the Soviet era. It was known as Gorky until 1990 and it was here that dissident scientist Andrei Sakharov was held under house arrest. Now the city hosts six World Cup matches and is teeming with tourists. That was unthinkable in the Soviet era and even rare now in a city that is seldom visited by outsiders. (Photo by Vadim Ghirda/AP Photo)

A communal worker removes the snow from steps next people dressed as pandas near the center of the Ukrainian capital Kiev, on November 14, 2018, during an heavy snowfall, the first one of this autumn season. (Photo by Sergei Supinsky/AFP Photo)

Workers pull apart a house in Khandyga, Russia, on February 2, 2018. The shifting ground caused by the uneven thawing of permafrost each summer causes buildings like this Soviet-era apartment house to sag and collapse. (Photo by Amos Chapple/Radio Free Europe/Radio Liberty)

A man tries to extinguish an advertisement board set on fire during a demonstration of French labour union members and workers, as France faces its 38th consecutive day of strike against French government's pensions reform plans, in Paris, France on January 11, 2020. (Photo by Gonzalo Fuentes/Reuters)

In this picture taken on January 5, 2022, people take part in a demonstration march after the Pyongyang City rally to carry out the decision of the 4th Plenary Meeting of the 8th Central Committee of the Workers' Party of Korea, at Kim Il Sung Square in Pyongyang. (Photo by Kim Won Jin/AFP Photo)

A worker pulls one of her colleagues on a sled, normally used to transport boxes, in the finish area of the alpine ski venue at the 2022 Winter Olympics, Wednesday, February 16, 2022, in the Yanqing district of Beijing. (Photo by Robert F. Bukaty/AP Photo)

Workers prepare the roof of a house to get installed solar power modules for producing heat on October 15, 2011 in Wessling, Germany. Germany has and is continuing to invest heavily in solar energy, both in the public and private sectors. The German government introduced a feed-in tariff with its Renewable Energy Act in 2000 that guarantees homeowners a minimum rate for selling electricity from renewable energy sources into the nation's electricity grid. (Photo by Alexandra Beier/Getty Images)