A person walks by an Ocean Rebellion activist taking part in a demonstration outside Department for Environment, Food and Rural Affairs (DEFRA) in London, Britain on September 15, 2021. (Photo by Hannah McKay/Reuters)

Aoife Ni Heochaidh enjoys the sunrise as she welcomes winter solstice at the 5000-year-old stone age passage tomb of Newgrange in the Boyne Valley, as entry inside the chamber is closed for the second year due to coronavirus disease (COVID-19) pandemic, in Newgrange, Ireland, December 21, 2021. (Photo by Clodagh Kilcoyne/Reuters)

Steam comes out of the chimneys of the coal-fired power station Neurath near the Garzweiler open-cast coal mine in Luetzerath, Germany, Monday, October 25, 2021. The climate change conference COP26 will start next Sunday in Glasgow, Scotland. (Photo by Michael Probst/AP Photo)

A Lord Krishna devotee is made up before the start of the Festival of Chariots, Ratha-yatra, held by the community of the Krishna Consciousness to honour Jagannatha, the Lord of the Universe, in Budapest, Hungary, Saturday, June 29, 2019. (Photo by Szilard Koszticsak/MTI via AP Photo)

A robin perches on a spade handle in a garden on a rainy day in Lixwm, north Wales. Researchers said this week that when European robins are subjected to human-produced noise, their behaviour changes. (Photo by DGDImages/Alamy Live News)

A view through mist shows the Kirk of Saint Mary Magdalene in Primorsk, Leningrad Region, Russia on March 24, 2019. (Photo by Anton Vaganov/Reuters)

An Algerian demonstrator wearing face paint in the colours of the national flag takes part in an anti-government demonstration in the capital Algiers on November 1, 2019. Demonstrators converged on Algiers in their thousands for a massive anti-government rally called to coincide with official celebrations of the anniversary of the war that won Algeria's independence from France. (Photo by Ryad Kramdi/AFP Photo)

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)