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 plane battling the Ferguson Fire passes the setting sun in unincorporated Mariposa County Calif., near Yosemite National Park on Sunday, July 15, 2018. (Photo by Noah Berger/AP Photo)

Climbers place a huge 80x80 metres (262x262 feet) Swiss national flag on the western face of the north-eastern Swiss landmark Mount Saentis, Switzerland on July 31, 2018. (Photo by Arnd Wiegmann/Reuters)

Farmer Ash Whitney stands in the middle of a dried-up dam in a drought-effected paddock on his property located west of the town of Gunnedah in New South Wales, Australia, June 3, 2018. “I have been here all my life, and this drought is feeling like it will be around a while”, said Whitney. (Photo by David Gray/Reuters)

Elderly women wait for customers as they sell their self-made food products at a street market, with a graffiti depicting Russian President Vladimir Putin on the wall of a house seen in the background, in the town of Kashira, outside Moscow, Russia on October 10, 2017. (Photo by Andrey Volkov/Reuters)

Arnaq Egede walks to the potato field on her family's farm on July 31, 2013 in Qaqortoq, Greenland. The farm, the largest in Greenland, has seen an extended crop growing season due to climate change. (Photo by Joe Raedle/Getty Images)

A 6-week old Fennec fox, the smallest species of foxes, and a native to the Sahara desert in Africa, looks as its mother eats in the Ramat Gan Safari Park near Tel Aviv, Israel, Sunday, November 6, 2016. Sagit Horowitz, the safari spokeswoman said four Fennec foxes were born about six weeks ago. (Photo by Ariel Schalit/AP Photo)

Pakistan girls make selfies holding a Pakistan-made weapon displayed at the four-day International Defence Exhibition and Seminar (IDEAS) 2016 in Karachi, Pakistan, Wednesday, November 23, 2016. (Photo by Shakil Adil/AP Photo)