Competitors in the Big Air challenge at the Proryv-2016 festival of extreme sports in Moscow, Russia on March 27, 2016. (Photo by Xinhua/Rex Features/Shutterstock)

A man stands next to a barricade blocking a road during a protest calling on the government to help ease the economic effects of an harmful algal bloom that had affected their livelihoods at Chiloe island in Chile, May 6, 2016. (Photo by Pablo Sanhueza/Reuters)

A Hindu devotee lies on a road as she worships the Sun god during the religious festival of Chhath Puja in Kolkata, India October 26, 2017. (Photo by Rupak De Chowdhuri/Reuters)

A US Marine leads two Viet Cong suspects in restraints during the Tet Offensive on February 20, 1967. (Photo by Bettmann Archive/Getty Images)

(L-R) A man nicknamed "Barcelona", Alexey Bolotov and Alexey Jakushin drink vodka as they travel by a pioneer motorised railcar on their way to Kalach, Sverdlovsk region, Russia October 18, 2015. The "pioneer," a light auxiliary rail vehicle, is a popular form of transport among people who live along the Alapayevsk railway. In a remote corner of the Urals region at the end of a narrow-gauge railway is Kalach, population about a dozen. Three decades ago 600 people called the village home, but the local forestry industry suffered as the former Soviet Union imploded and people moved away in search of work. In Kalach today there are no telephones, no mobile reception and only a few hours of electricity a day. (Photo by Maxim Zmeyev/Reuters)

People wearing bear furs perform during a festival of New Year ritual dances attended by hundreds in Comanesti, northern Romania, Wednesday, December 30 2015. In pre-Christian rural traditions, dancers wearing colored costumes or animal furs, toured from house to house in villages singing and dancing to ward off evil, in the present the tradition has moved to Romania's cities too, where dancers travel to perform the ritual for money. (Photo by Vadim Ghirda/AP Photo)

A participant blows on yellow powder held in her hand during a Holi Party before the Gay Pride Parade in Barcelona on July 9, 2016. (Photo by Lluis Gene/AFP Photo)

A student participates in celebrations ahead of the Janmashtami festival, which marks the birth anniversary of Lord Krishna in Mumbai, India, August 23, 2016. (Photo by Danish Siddiqui/Reuters)